Sandkassa

From Maria GDK Wiki
Jump to navigation Jump to search

Her skal Mari leke. Hvis hun gidder....

Da leker JEG her. For det gidder jeg.

Intern link: #Preparing for creation of Maria layers

Intern link skjult med tekst: Teksten

Gigantisk haug med kode:

This section describes how to create a basic map application, with fixed map type - displaying tracks from a track service.

This example is made to run with Maria GDK Version 2.0, with .NETFramework version 4.5. Sample code for this example is found in the MariaBasicMapClient project of the SampleProjects solution.

def lag_mat(ingredienser):
   komfyr.stek()

Noen bilder

Creating the Map Client Window

Create a WPF Window (main application window or sub window) - MariaWpfWindow - to be used for your map client.
For building Maria GDK clients in Windows forms applications, see Maria Windows-Forms Client.


Including MariaUserControl

Add the MariaUserControl to the xaml of your window, name of your choice, optionally including properties for the integrated map controls.

<Window x:Class="BasicMapClient.MariaWpfWindow"
 . . . 
 xmlns:MariaUserControl= "clr-namespace:TPG.Maria.MariaUserControl; assembly=TPG.Maria.MariaUserControl"
 Title="MariaWpfWindow" Height="550" Width="525" >
 <Grid>
 <MariaUserControl:MariaUserControl Name="MariaCtrl"
                                    IsMiniMapVisible="True"
                                    IsPanNavigationVisible="True"
                                    IsScaleBarVisible="True"
                                    IsRulerVisible="True"
                                    />
  </Grid>
</Window>

Main view model

Create a class (MariaWindowViewModel) for communication with the Maria component.

In the constructor of your window (MariaWpfWindow) Set the data context of your client window to be this class.

public MariaWpfWindow()
{
  InitializeComponent();
  DataContext = new MariaWindowViewModel();
}

Handle the WindowClosing event

In the window holding your MariaUserControl (MariaWpfWindow), implement an event handler for the WindowClosing event, disposing the MariaUserControl object and the MapLayerManager object used by the map layers.

In the XAML :

<Window x:Class="BasicMapClient.MariaWpfWindow"
 . . . 
 Title="MariaWpfWindow" Height="550" Width="525" Closing="WindowClosing">
   <Grid>
      <MariaUserControl:MariaUserControl
      . . .

In the code behind:

private void WindowClosing(object sender, System.ComponentModel.CancelEventArgs e)
{
  MariaCtrl.Dispose();
  ((IDisposable)DataContext).Dispose();
}

Preparing for creation of Maria layers

In the main view model class, MariaWindowViewModel, create an auto property to hold a list of Maria layers, Layers, and add a constructor, initializing the propery.

public ObservableCollection<IMariaLayer>Layers { get; set; }

internal MariaWindowViewModel()
{
    Layers = new ObservableCollection<IMariaLayer>();
}

Then, bind the Layers property of the MariaUserControl to this list.

<MariaUserControl:MariaUserControl Name="MariaCtrl"
                                   Layers="{Binding Layers}"
                                   IsMiniMapVisible="True"
                                   IsPanNavigationVisible="True"
                                   IsScaleBarVisible="True"
                                   IsRulerVisible="True"
                                   />


Layer interaction in general

For each of the desired layers (will be described in detail for each layer type):

  • Create an instance of the corresponding GDK layer class
  • Add the created layer to the MariaWindowViewModel Layers property.
  • Create a separate view model class for each layer (may be skipped, if few layers)
  • Add event handler(s) for the LayerInitialized event(s).

The layers are accessed programmatically from your application through the different GDK layer interfaces.


Note:

  • Rendering of the layers will be in the same order as they are in the Layers property.
  • No access should be performed against the layer until the LayerInitialized event has been called.

Service configuration

To enable the service related layers to receive information from their services, they need to establish connections! One way of doing this is by specification in the application configuration (app.config).

Here is a service connection configuration example with connection info for some of the Maria GDK services,within the system.serviceModel tag.
For further details on how to administrate Maria GDK services, refer to the system documentation.

  <system.serviceModel>
    <bindings>
      <basicHttpBinding>
        <binding name="myHttpBinding" 
                 maxBufferSize="2147483647" 
                 maxReceivedMessageSize="2147483647" 
                 closeTimeout="00:10:00" openTimeout="00:10:00" 
                 receiveTimeout="00:10:00" sendTimeout="00:10:00">
          <readerQuotas maxArrayLength="2147483647" />
        </binding>
      </basicHttpBinding>
    </bindings>
    
    <client>
      <!-- Catalog service -->
      <endpoint name="MapCatalogService"
                address="http://localhost:9008/catalog"
                contract="TPG.GeoFramework.MapServiceInterfaces.IMapCatalogService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding"/>

      <!-- Template service -->
      <endpoint name="TemplateService"
                address="http://localhost:9008/maptemplates"
                contract="TPG.GeoFramework.MapTemplateServiceContracts.IMapTemplateService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding"/>

      <!-- Track service -->
      <endpoint name="TrackService"
                address="http://localhost:9008/tracks"
                contract="TPG.GeoFramework.TrackServiceInterfaces.IMariaTrackService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding"/>

      <!-- Enhanced Elevation service -->
      <endpoint name="EnahncedElevationService"
                address="http://localhost:9008/enhancedElevation"
                contract="TPG.EnhancedElevationServiceClient.IEnhancedElevationService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding"/>

      <!-- Location service -->
      <endpoint name="LocationService"
                address="http://localhost:9008/location/geoloc"
                contract="TPG.GeoFramework.LocationServiceInterfaces.ILocationService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding"
                behaviorConfiguration="myEndpointBehavior"/>

      <!-- Draw object service -->
      <endpoint name="DrawObjectService"
                address="http://localhost:9008/drawobjects"
                contract="TPG.GeoFramework.DrawObjectServiceInterfaces.IDrawObjectService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding"/>

      <!-- Geo Fencing Service -->
      <endpoint name="GeoFencingService/DataManager"
                address="http://localhost:9008/GeoFencingService/DataManager"
                contract="TPG.GeoFramework.GeoFencingServiceInterfaces.IDataManagerService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding" />

      <endpoint name="GeoFencingService/FenceRule"
                address="http://localhost:9008/GeoFencingService/FenceRule"
                contract="TPG.GeoFramework.GeoFencingServiceInterfaces.IGeoFencingRuleService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding" />

      <endpoint name="GeoFencingService/NotificationHandling"
                address="http://localhost:9008/GeoFencingService/NotificationHandling"
                contract="TPG.GeoFramework.GeoFencingServiceInterfaces.INotificationHandlingService"
                binding="basicHttpBinding"
                bindingConfiguration="myHttpBinding" />

    </client>
    <behaviors>
      <endpointBehaviors>
        <behavior name="myEndpointBehavior">
          <dataContractSerializer maxItemsInObjectGraph="2147483647" />
        </behavior>
      </endpointBehaviors>
    </behaviors>
    <extensions></extensions>
  </system.serviceModel>

Creating a Map Layer with Map Service Connection

The map layer is accessed programmatically through the map layer interface, IMariaMapLayer, and the extended map layer interface IMariaExtendedMapLayer .

  • For this part you will need to include TPG.Maria.MapLayer NuGet package.

Create a view model class (MapViewModel) to handle intaractions toward the map layer, and add the following variables and properties:

private readonly IMariaMapLayer _mapLayer;

public IMariaMapLayer MiniMapLayer { get; set; }
public GeoPos CenterPosition { get; set; }
public double Scale { get; set; }

Create the MapViewModel constructor, initializing map and minimap event handling:

public MapViewModel(IMariaMapLayer mapLayer, IMariaMapLayer miniMapLayer)
{
    _mapLayer = mapLayer;
    _mapLayer.LayerInitialized += OnMapLayerInitialized;
    
    MiniMapLayer = miniMapLayer;
    MiniMapLayer.LayerInitialized += OnMiniMapLayerInitialized;
}

Add the LayerInitialized event handlers for the map and mini map:

private void OnMapLayerInitialized()
{
    Scale = 50000;
    CenterPosition = new GeoPos(60, 10);

    _mapLayer.ActiveMapTemplate = PreferredMapTemplate();
}
private void OnMiniMapLayerInitialized()
{
    MiniMapLayer.ActiveMapTemplate = PreferredMapTemplate();
}

private MapTemplate PreferredMapTemplate()
{
    var preferred = "WorldMap";
    foreach (var template in _mapLayer.ActiveMapTemplates)
    {
        if (template.Name == preferred)
            return template;
    }
    return _mapLayer.ActiveMapTemplates.Any() ? _mapLayer.ActiveMapTemplates.Last() : null;
}

Verify that your app.config file contains endpoint definitions for the MapCatalogService and the TemplateService, as described in the Service Configuration section.

Then, include the MapViewModel in the main view model (MariaWindowViewModel).

Declarations:

public MapViewModel MapViewModel { get; set; }

private IMariaMapLayer _mapLayer;
private MapLayer _miniMapLayer;

and in the constructor

. . .

// Service connection specified by app.config
IMariaMapLayerManager mapLayerManager = new MariaMapLayerManager();

_mapLayer = new MapLayer(mapCatalogServiceClient, mapTemplateServiceClient);
_miniMapLayer = new MapLayer(mapCatalogServiceClient, mapTemplateServiceClient);

MapViewModel = new MapViewModel(_mapLayer, _miniMapLayer);
Layers.Add(_mapLayer);

Update MariaUserControl binding

<MariaUserControl:MariaUserControl Name="MariaCtrl"
                                   Layers="{Binding Layers}"
                                   IsMiniMapVisible="True"
                                   IsPanNavigationVisible="True" 
                                   IsScaleBarVisible="True" 
                                   IsRulerVisible="True" 
                                   CenterScale="{Binding MapViewModel.Scale}" 
                                   CenterPosition="{Binding MapViewModel.CenterPosition}" 
                                   MiniMapLayer="{Binding MapViewModel.MiniMapLayer}"     
                                   />


Creating Track Layer with Track Service Connection

Key information:

  • The track layer is accessed programmatically through the track layer interface IMariaTrackLayer and the extended track layer interface IMariaExtendedTrackLayer.
  • For this part you will need to add the TPG.Maria.TrackLayer NuGet package.

Create a view model class (TrackViewModel) for the track layer:

public class TrackViewModel 
{    
}

Add the following local variable

private readonly IMariaTrackLayer _trackLayer;

Add the TrackViewModel constructor

public TrackViewModel(IMariaTrackLayer trackLayer)
{
    _trackLayer = trackLayer;
    _trackLayer.LayerInitialized += OnTrackLayerInitialized;
}

Implement the OnInitialized event handler (OnTrackLayerInitialized) For the TrackList value, use a track list available in your Track Service.

private void OnTrackLayerInitialized()
{  
    _trackLayer.TrackLists = new ObservableCollection<string> { "ais.test" };
    _trackLayer.TrackServices = new ObservableCollection<IMariaService> 
          {
              new MariaService("TrackService")
          };

    if (_trackLayer.TrackServices.Count > 0)
    {
        _trackLayer.ActiveTrackService = _trackLayer.TrackServices[0];
        _trackLayer.ActiveTrackList = _trackLayer.TrackLists[0];
    }
}

Make sure that your app.config file contains endpoint definitions for the TrackService, as described in the Service Configuration section.

Then, include the TrackViewModel in the main view model (MariaWindowViewModel).

Declarations:

private readonly IMariaTrackLayer _trackLayer;
public TrackViewModel TrackViewModel { get; set; }

and in the constructor

_trackLayer = new TPG.Maria.TrackLayer.TrackLayer();
TrackViewModel = new TrackViewModel(_trackLayer);
Layers.Add(_trackLayer);


Run: In addition to map information and mini map, the application should now include tracks from the specified track list of a Track Service, and you should be able to select tracks!




// ZipOutputStream.cs
//
// ------------------------------------------------------------------
//
// Copyright (c) 2009 Dino Chiesa.
// All rights reserved.
//
// This code module is part of DotNetZip, a zipfile class library.
//
// ------------------------------------------------------------------
//
// This code is licensed under the Microsoft Public License.
// See the file License.txt for the license details.
// More info on: http://dotnetzip.codeplex.com
//
// ------------------------------------------------------------------
//
// last saved (in emacs):
// Time-stamp: <2011-July-28 06:34:30>
//
// ------------------------------------------------------------------
//
// This module defines the ZipOutputStream class, which is a stream metaphor for
// generating zip files.  This class does not depend on Ionic.Zip.ZipFile, but rather
// stands alongside it as an alternative "container" for ZipEntry.  It replicates a
// subset of the properties, including these:
//
//  - Comment
//  - Encryption
//  - Password
//  - CodecBufferSize
//  - CompressionLevel
//  - CompressionMethod
//  - EnableZip64 (UseZip64WhenSaving)
//  - IgnoreCase (!CaseSensitiveRetrieval)
//
// It adds these novel methods:
//
//  - PutNextEntry
//
//
// ------------------------------------------------------------------
//

using System;
using System.Threading;
using System.Collections.Generic;
using System.IO;
using Ionic.Zip;

namespace Ionic.Zip
{
    /// <summary>
    ///   Provides a stream metaphor for generating zip files.
    /// </summary>
    ///
    /// <remarks>
    /// <para>
    ///   This class writes zip files, as defined in the <see
    ///   href="http://www.pkware.com/documents/casestudies/APPNOTE.TXT">specification
    ///   for zip files described by PKWare</see>.  The compression for this
    ///   implementation is provided by a managed-code version of Zlib, included with
    ///   DotNetZip in the classes in the Ionic.Zlib namespace.
    /// </para>
    ///
    /// <para>
    ///   This class provides an alternative programming model to the one enabled by the
    ///   <see cref="ZipFile"/> class. Use this when creating zip files, as an
    ///   alternative to the <see cref="ZipFile"/> class, when you would like to use a
    ///   <c>Stream</c> type to write the zip file.
    /// </para>
    ///
    /// <para>
    ///   Both the <c>ZipOutputStream</c> class and the <c>ZipFile</c> class can be used
    ///   to create zip files. Both of them support many of the common zip features,
    ///   including Unicode, different compression levels, and ZIP64.   They provide
    ///   very similar performance when creating zip files.
    /// </para>
    ///
    /// <para>
    ///   The <c>ZipFile</c> class is generally easier to use than
    ///   <c>ZipOutputStream</c> and should be considered a higher-level interface.  For
    ///   example, when creating a zip file via calls to the <c>PutNextEntry()</c> and
    ///   <c>Write()</c> methods on the <c>ZipOutputStream</c> class, the caller is
    ///   responsible for opening the file, reading the bytes from the file, writing
    ///   those bytes into the <c>ZipOutputStream</c>, setting the attributes on the
    ///   <c>ZipEntry</c>, and setting the created, last modified, and last accessed
    ///   timestamps on the zip entry. All of these things are done automatically by a
    ///   call to <see cref="ZipFile.AddFile(string,string)">ZipFile.AddFile()</see>.
    ///   For this reason, the <c>ZipOutputStream</c> is generally recommended for use
    ///   only when your application emits arbitrary data, not necessarily data from a
    ///   filesystem file, directly into a zip file, and does so using a <c>Stream</c>
    ///   metaphor.
    /// </para>
    ///
    /// <para>
    ///   Aside from the differences in programming model, there are other
    ///   differences in capability between the two classes.
    /// </para>
    ///
    /// <list type="bullet">
    ///   <item>
    ///     <c>ZipFile</c> can be used to read and extract zip files, in addition to
    ///     creating zip files. <c>ZipOutputStream</c> cannot read zip files. If you want
    ///     to use a stream to read zip files, check out the <see cref="ZipInputStream"/> class.
    ///   </item>
    ///
    ///   <item>
    ///     <c>ZipOutputStream</c> does not support the creation of segmented or spanned
    ///     zip files.
    ///   </item>
    ///
    ///   <item>
    ///     <c>ZipOutputStream</c> cannot produce a self-extracting archive.
    ///   </item>
    /// </list>
    ///
    /// <para>
    ///   Be aware that the <c>ZipOutputStream</c> class implements the <see
    ///   cref="System.IDisposable"/> interface.  In order for
    ///   <c>ZipOutputStream</c> to produce a valid zip file, you use use it within
    ///   a using clause (<c>Using</c> in VB), or call the <c>Dispose()</c> method
    ///   explicitly.  See the examples for how to employ a using clause.
    /// </para>
    ///
    /// <para>
    ///   Also, a note regarding compression performance: On the desktop .NET
    ///   Framework, DotNetZip can use a multi-threaded compression implementation
    ///   that provides significant speed increases on large files, over 300k or so,
    ///   at the cost of increased memory use at runtime.  (The output of the
    ///   compression is almost exactly the same size).  But, the multi-threaded
    ///   approach incurs a performance hit on smaller files. There's no way for the
    ///   ZipOutputStream to know whether parallel compression will be beneficial,
    ///   because the ZipOutputStream does not know how much data you will write
    ///   through the stream.  You may wish to set the <see
    ///   cref="ParallelDeflateThreshold"/> property to zero, if you are compressing
    ///   large files through <c>ZipOutputStream</c>.  This will cause parallel
    ///   compression to be used, always.
    /// </para>
    /// </remarks>
    public class ZipOutputStream : Stream
    {
        /// <summary>
        ///   Create a ZipOutputStream, wrapping an existing stream.
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   The <see cref="ZipFile"/> class is generally easier to use when creating
        ///   zip files. The ZipOutputStream offers a different metaphor for creating a
        ///   zip file, based on the <see cref="System.IO.Stream"/> class.
        /// </para>
        ///
        /// </remarks>
        ///
        /// <param name="stream">
        /// The stream to wrap. It must be writable. This stream will be closed at
        /// the time the ZipOutputStream is closed.
        /// </param>
        ///
        /// <example>
        ///
        ///   This example shows how to create a zip file, using the
        ///   ZipOutputStream class.
        ///
        /// <code lang="C#">
        /// private void Zipup()
        /// {
        ///     if (filesToZip.Count == 0)
        ///     {
        ///         System.Console.WriteLine("Nothing to do.");
        ///         return;
        ///     }
        ///
        ///     using (var raw = File.Open(_outputFileName, FileMode.Create, FileAccess.ReadWrite ))
        ///     {
        ///         using (var output= new ZipOutputStream(raw))
        ///         {
        ///             output.Password = "VerySecret!";
        ///             output.Encryption = EncryptionAlgorithm.WinZipAes256;
        ///
        ///             foreach (string inputFileName in filesToZip)
        ///             {
        ///                 System.Console.WriteLine("file: {0}", inputFileName);
        ///
        ///                 output.PutNextEntry(inputFileName);
        ///                 using (var input = File.Open(inputFileName, FileMode.Open, FileAccess.Read, FileShare.Read | FileShare.Write ))
        ///                 {
        ///                     byte[] buffer= new byte[2048];
        ///                     int n;
        ///                     while ((n= input.Read(buffer,0,buffer.Length)) > 0)
        ///                     {
        ///                         output.Write(buffer,0,n);
        ///                     }
        ///                 }
        ///             }
        ///         }
        ///     }
        /// }
        /// </code>
        ///
        /// <code lang="VB">
        /// Private Sub Zipup()
        ///     Dim outputFileName As String = "XmlData.zip"
        ///     Dim filesToZip As String() = Directory.GetFiles(".", "*.xml")
        ///     If (filesToZip.Length = 0) Then
        ///         Console.WriteLine("Nothing to do.")
        ///     Else
        ///         Using raw As FileStream = File.Open(outputFileName, FileMode.Create, FileAccess.ReadWrite)
        ///             Using output As ZipOutputStream = New ZipOutputStream(raw)
        ///                 output.Password = "VerySecret!"
        ///                 output.Encryption = EncryptionAlgorithm.WinZipAes256
        ///                 Dim inputFileName As String
        ///                 For Each inputFileName In filesToZip
        ///                     Console.WriteLine("file: {0}", inputFileName)
        ///                     output.PutNextEntry(inputFileName)
        ///                     Using input As FileStream = File.Open(inputFileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)
        ///                         Dim n As Integer
        ///                         Dim buffer As Byte() = New Byte(2048) {}
        ///                         Do While (n = input.Read(buffer, 0, buffer.Length) > 0)
        ///                             output.Write(buffer, 0, n)
        ///                         Loop
        ///                     End Using
        ///                 Next
        ///             End Using
        ///         End Using
        ///     End If
        /// End Sub
        /// </code>
        /// </example>
        public ZipOutputStream(Stream stream) : this(stream, false) { }


        /// <summary>
        ///   Create a ZipOutputStream that writes to a filesystem file.
        /// </summary>
        ///
        /// <remarks>
        ///   The <see cref="ZipFile"/> class is generally easier to use when creating
        ///   zip files. The ZipOutputStream offers a different metaphor for creating a
        ///   zip file, based on the <see cref="System.IO.Stream"/> class.
        /// </remarks>
        ///
        /// <param name="fileName">
        ///   The name of the zip file to create.
        /// </param>
        ///
        /// <example>
        ///
        ///   This example shows how to create a zip file, using the
        ///   ZipOutputStream class.
        ///
        /// <code lang="C#">
        /// private void Zipup()
        /// {
        ///     if (filesToZip.Count == 0)
        ///     {
        ///         System.Console.WriteLine("Nothing to do.");
        ///         return;
        ///     }
        ///
        ///     using (var output= new ZipOutputStream(outputFileName))
        ///     {
        ///         output.Password = "VerySecret!";
        ///         output.Encryption = EncryptionAlgorithm.WinZipAes256;
        ///
        ///         foreach (string inputFileName in filesToZip)
        ///         {
        ///             System.Console.WriteLine("file: {0}", inputFileName);
        ///
        ///             output.PutNextEntry(inputFileName);
        ///             using (var input = File.Open(inputFileName, FileMode.Open, FileAccess.Read,
        ///                                          FileShare.Read | FileShare.Write ))
        ///             {
        ///                 byte[] buffer= new byte[2048];
        ///                 int n;
        ///                 while ((n= input.Read(buffer,0,buffer.Length)) > 0)
        ///                 {
        ///                     output.Write(buffer,0,n);
        ///                 }
        ///             }
        ///         }
        ///     }
        /// }
        /// </code>
        ///
        /// <code lang="VB">
        /// Private Sub Zipup()
        ///     Dim outputFileName As String = "XmlData.zip"
        ///     Dim filesToZip As String() = Directory.GetFiles(".", "*.xml")
        ///     If (filesToZip.Length = 0) Then
        ///         Console.WriteLine("Nothing to do.")
        ///     Else
        ///         Using output As ZipOutputStream = New ZipOutputStream(outputFileName)
        ///             output.Password = "VerySecret!"
        ///             output.Encryption = EncryptionAlgorithm.WinZipAes256
        ///             Dim inputFileName As String
        ///             For Each inputFileName In filesToZip
        ///                 Console.WriteLine("file: {0}", inputFileName)
        ///                 output.PutNextEntry(inputFileName)
        ///                 Using input As FileStream = File.Open(inputFileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite)
        ///                     Dim n As Integer
        ///                     Dim buffer As Byte() = New Byte(2048) {}
        ///                     Do While (n = input.Read(buffer, 0, buffer.Length) > 0)
        ///                         output.Write(buffer, 0, n)
        ///                     Loop
        ///                 End Using
        ///             Next
        ///         End Using
        ///     End If
        /// End Sub
        /// </code>
        /// </example>
        public ZipOutputStream(String fileName)
        {
            Stream stream = File.Open(fileName, FileMode.Create, FileAccess.ReadWrite, FileShare.None);
            _Init(stream, false, fileName);
        }


        /// <summary>
        ///   Create a ZipOutputStream.
        /// </summary>
        ///
        /// <remarks>
        ///   See the documentation for the <see
        ///   cref="ZipOutputStream(Stream)">ZipOutputStream(Stream)</see>
        ///   constructor for an example.
        /// </remarks>
        ///
        /// <param name="stream">
        ///   The stream to wrap. It must be writable.
        /// </param>
        ///
        /// <param name="leaveOpen">
        ///   true if the application would like the stream
        ///   to remain open after the <c>ZipOutputStream</c> has been closed.
        /// </param>
        public ZipOutputStream(Stream stream, bool leaveOpen)
        {
            _Init(stream, leaveOpen, null);
        }

        private void _Init(Stream stream, bool leaveOpen, string name)
        {
            // workitem 9307
            _outputStream = stream.CanRead ? stream : new CountingStream(stream);
            CompressionLevel = Ionic.Zlib.CompressionLevel.Default;
            CompressionMethod = Ionic.Zip.CompressionMethod.Deflate;
            _encryption = EncryptionAlgorithm.None;
            _entriesWritten = new Dictionary<String, ZipEntry>(StringComparer.Ordinal);
            _zip64 = Zip64Option.Never;
            _leaveUnderlyingStreamOpen = leaveOpen;
            Strategy = Ionic.Zlib.CompressionStrategy.Default;
            _name = name ?? "(stream)";
#if !NETCF
            ParallelDeflateThreshold = -1L;
#endif
        }


        /// <summary>Provides a string representation of the instance.</summary>
        /// <remarks>
        ///   <para>
        ///     This can be useful for debugging purposes.
        ///   </para>
        /// </remarks>
        /// <returns>a string representation of the instance.</returns>
        public override String ToString()
        {
            return String.Format ("ZipOutputStream::{0}(leaveOpen({1})))", _name, _leaveUnderlyingStreamOpen);
        }


        /// <summary>
        ///   Sets the password to be used on the <c>ZipOutputStream</c> instance.
        /// </summary>
        ///
        /// <remarks>
        ///
        /// <para>
        ///   When writing a zip archive, this password is applied to the entries, not
        ///   to the zip archive itself. It applies to any <c>ZipEntry</c> subsequently
        ///   written to the <c>ZipOutputStream</c>.
        /// </para>
        ///
        /// <para>
        ///   Using a password does not encrypt or protect the "directory" of the
        ///   archive - the list of entries contained in the archive.  If you set the
        ///   <c>Password</c> property, the password actually applies to individual
        ///   entries that are added to the archive, subsequent to the setting of this
        ///   property.  The list of filenames in the archive that is eventually created
        ///   will appear in clear text, but the contents of the individual files are
        ///   encrypted.  This is how Zip encryption works.
        /// </para>
        ///
        /// <para>
        ///   If you set this property, and then add a set of entries to the archive via
        ///   calls to <c>PutNextEntry</c>, then each entry is encrypted with that
        ///   password.  You may also want to change the password between adding
        ///   different entries. If you set the password, add an entry, then set the
        ///   password to <c>null</c> (<c>Nothing</c> in VB), and add another entry, the
        ///   first entry is encrypted and the second is not.
        /// </para>
        ///
        /// <para>
        ///   When setting the <c>Password</c>, you may also want to explicitly set the <see
        ///   cref="Encryption"/> property, to specify how to encrypt the entries added
        ///   to the ZipFile.  If you set the <c>Password</c> to a non-null value and do not
        ///   set <see cref="Encryption"/>, then PKZip 2.0 ("Weak") encryption is used.
        ///   This encryption is relatively weak but is very interoperable. If
        ///   you set the password to a <c>null</c> value (<c>Nothing</c> in VB),
        ///   <c>Encryption</c> is reset to None.
        /// </para>
        ///
        /// <para>
        ///   Special case: if you wrap a ZipOutputStream around a non-seekable stream,
        ///   and use encryption, and emit an entry of zero bytes, the <c>Close()</c> or
        ///   <c>PutNextEntry()</c> following the entry will throw an exception.
        /// </para>
        ///
        /// </remarks>
        public String Password
        {
            set
            {
                if (_disposed)
                {
                    _exceptionPending = true;
                    throw new System.InvalidOperationException("The stream has been closed.");
                }

                _password = value;
                if (_password == null)
                {
                    _encryption = EncryptionAlgorithm.None;
                }
                else if (_encryption == EncryptionAlgorithm.None)
                {
                    _encryption = EncryptionAlgorithm.PkzipWeak;
                }
            }
        }


        /// <summary>
        ///   The Encryption to use for entries added to the <c>ZipOutputStream</c>.
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   The specified Encryption is applied to the entries subsequently
        ///   written to the <c>ZipOutputStream</c> instance.
        /// </para>
        ///
        /// <para>
        ///   If you set this to something other than
        ///   EncryptionAlgorithm.None, you will also need to set the
        ///   <see cref="Password"/> to a non-null, non-empty value in
        ///   order to actually get encryption on the entry.
        /// </para>
        ///
        /// </remarks>
        ///
        /// <seealso cref="Password">ZipOutputStream.Password</seealso>
        /// <seealso cref="Ionic.Zip.ZipEntry.Encryption">ZipEntry.Encryption</seealso>
        public EncryptionAlgorithm Encryption
        {
            get
            {
                return _encryption;
            }
            set
            {
                if (_disposed)
                {
                    _exceptionPending = true;
                    throw new System.InvalidOperationException("The stream has been closed.");
                }
                if (value == EncryptionAlgorithm.Unsupported)
                {
                    _exceptionPending = true;
                    throw new InvalidOperationException("You may not set Encryption to that value.");
                }
                _encryption = value;
            }
        }


        /// <summary>
        ///   Size of the work buffer to use for the ZLIB codec during compression.
        /// </summary>
        ///
        /// <remarks>
        ///   Setting this may affect performance.  For larger files, setting this to a
        ///   larger size may improve performance, but I'm not sure.  Sorry, I don't
        ///   currently have good recommendations on how to set it.  You can test it if
        ///   you like.
        /// </remarks>
        public int CodecBufferSize
        {
            get;
            set;
        }


        /// <summary>
        ///   The compression strategy to use for all entries.
        /// </summary>
        ///
        /// <remarks>
        ///   Set the Strategy used by the ZLIB-compatible compressor, when compressing
        ///   data for the entries in the zip archive. Different compression strategies
        ///   work better on different sorts of data. The strategy parameter can affect
        ///   the compression ratio and the speed of compression but not the correctness
        ///   of the compresssion.  For more information see <see
        ///   cref="Ionic.Zlib.CompressionStrategy "/>.
        /// </remarks>
        public Ionic.Zlib.CompressionStrategy Strategy
        {
            get;
            set;
        }


        /// <summary>
        ///   The type of timestamp attached to the ZipEntry.
        /// </summary>
        ///
        /// <remarks>
        ///   Set this in order to specify the kind of timestamp that should be emitted
        ///   into the zip file for each entry.
        /// </remarks>
        public ZipEntryTimestamp Timestamp
        {
            get
            {
                return _timestamp;
            }
            set
            {
                if (_disposed)
                {
                    _exceptionPending = true;
                    throw new System.InvalidOperationException("The stream has been closed.");
                }
                _timestamp = value;
            }
        }


        /// <summary>
        ///   Sets the compression level to be used for entries subsequently added to
        ///   the zip archive.
        /// </summary>
        ///
        /// <remarks>
        ///  <para>
        ///    Varying the compression level used on entries can affect the
        ///    size-vs-speed tradeoff when compression and decompressing data streams
        ///    or files.
        ///  </para>
        ///
        ///  <para>
        ///    As with some other properties on the <c>ZipOutputStream</c> class, like <see
        ///    cref="Password"/>, and <see cref="Encryption"/>,
        ///    setting this property on a <c>ZipOutputStream</c>
        ///    instance will cause the specified <c>CompressionLevel</c> to be used on all
        ///    <see cref="ZipEntry"/> items that are subsequently added to the
        ///    <c>ZipOutputStream</c> instance.
        ///  </para>
        ///
        ///  <para>
        ///    If you do not set this property, the default compression level is used,
        ///    which normally gives a good balance of compression efficiency and
        ///    compression speed.  In some tests, using <c>BestCompression</c> can
        ///    double the time it takes to compress, while delivering just a small
        ///    increase in compression efficiency.  This behavior will vary with the
        ///    type of data you compress.  If you are in doubt, just leave this setting
        ///    alone, and accept the default.
        ///  </para>
        /// </remarks>
        public Ionic.Zlib.CompressionLevel CompressionLevel
        {
            get;
            set;
        }

        /// <summary>
        ///   The compression method used on each entry added to the ZipOutputStream.
        /// </summary>
        public Ionic.Zip.CompressionMethod CompressionMethod
        {
            get;
            set;
        }


        /// <summary>
        ///   A comment attached to the zip archive.
        /// </summary>
        ///
        /// <remarks>
        ///
        /// <para>
        ///   The application sets this property to specify a comment to be embedded
        ///   into the generated zip archive.
        /// </para>
        ///
        /// <para>
        ///   According to <see
        ///   href="http://www.pkware.com/documents/casestudies/APPNOTE.TXT">PKWARE's
        ///   zip specification</see>, the comment is not encrypted, even if there is a
        ///   password set on the zip file.
        /// </para>
        ///
        /// <para>
        ///   The specification does not describe how to indicate the encoding used
        ///   on a comment string. Many "compliant" zip tools and libraries use
        ///   IBM437 as the code page for comments; DotNetZip, too, follows that
        ///   practice.  On the other hand, there are situations where you want a
        ///   Comment to be encoded with something else, for example using code page
        ///   950 "Big-5 Chinese". To fill that need, DotNetZip will encode the
        ///   comment following the same procedure it follows for encoding
        ///   filenames: (a) if <see cref="AlternateEncodingUsage"/> is
        ///   <c>Never</c>, it uses the default encoding (IBM437). (b) if <see
        ///   cref="AlternateEncodingUsage"/> is <c>Always</c>, it always uses the
        ///   alternate encoding (<see cref="AlternateEncoding"/>). (c) if <see
        ///   cref="AlternateEncodingUsage"/> is <c>AsNecessary</c>, it uses the
        ///   alternate encoding only if the default encoding is not sufficient for
        ///   encoding the comment - in other words if decoding the result does not
        ///   produce the original string.  This decision is taken at the time of
        ///   the call to <c>ZipFile.Save()</c>.
        /// </para>
        ///
        /// </remarks>
        public string Comment
        {
            get { return _comment; }
            set
            {
                if (_disposed)
                {
                    _exceptionPending = true;
                    throw new System.InvalidOperationException("The stream has been closed.");
                }
                _comment = value;
            }
        }



        /// <summary>
        ///   Specify whether to use ZIP64 extensions when saving a zip archive.
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   The default value for the property is <see
        ///   cref="Zip64Option.Never"/>. <see cref="Zip64Option.AsNecessary"/> is
        ///   safest, in the sense that you will not get an Exception if a
        ///   pre-ZIP64 limit is exceeded.
        /// </para>
        ///
        /// <para>
        ///   You must set this property before calling <c>Write()</c>.
        /// </para>
        ///
        /// </remarks>
        public Zip64Option EnableZip64
        {
            get
            {
                return _zip64;
            }
            set
            {
                if (_disposed)
                {
                    _exceptionPending = true;
                    throw new System.InvalidOperationException("The stream has been closed.");
                }
                _zip64 = value;
            }
        }


        /// <summary>
        ///   Indicates whether ZIP64 extensions were used when saving the zip archive.
        /// </summary>
        ///
        /// <remarks>
        ///   The value is defined only after the <c>ZipOutputStream</c> has been closed.
        /// </remarks>
        public bool OutputUsedZip64
        {
            get
            {
                return _anyEntriesUsedZip64 || _directoryNeededZip64;
            }
        }


        /// <summary>
        ///   Whether the ZipOutputStream should use case-insensitive comparisons when
        ///   checking for uniqueness of zip entries.
        /// </summary>
        ///
        /// <remarks>
        ///   <para>
        ///   Though the zip specification doesn't prohibit zipfiles with duplicate
        ///   entries, Sane zip files have no duplicates, and the DotNetZip library
        ///   cannot create zip files with duplicate entries. If an application attempts
        ///   to call <see cref="PutNextEntry(String)"/> with a name that duplicates one
        ///   already used within the archive, the library will throw an Exception.
        ///   </para>
        ///   <para>
        ///   This property allows the application to specify whether the
        ///   ZipOutputStream instance considers ordinal case when checking for
        ///   uniqueness of zip entries.
        ///   </para>
        /// </remarks>
        public bool IgnoreCase
        {
          get
          {
              return !_DontIgnoreCase;
          }

          set
          {
              _DontIgnoreCase = !value;
          }

        }


        /// <summary>
        ///   Indicates whether to encode entry filenames and entry comments using
        ///   Unicode (UTF-8).
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   <see href="http://www.pkware.com/documents/casestudies/APPNOTE.TXT">The
        ///   PKWare zip specification</see> provides for encoding file names and file
        ///   comments in either the IBM437 code page, or in UTF-8.  This flag selects
        ///   the encoding according to that specification.  By default, this flag is
        ///   false, and filenames and comments are encoded into the zip file in the
        ///   IBM437 codepage.  Setting this flag to true will specify that filenames
        ///   and comments that cannot be encoded with IBM437 will be encoded with
        ///   UTF-8.
        /// </para>
        ///
        /// <para>
        ///   Zip files created with strict adherence to the PKWare specification with
        ///   respect to UTF-8 encoding can contain entries with filenames containing
        ///   any combination of Unicode characters, including the full range of
        ///   characters from Chinese, Latin, Hebrew, Greek, Cyrillic, and many other
        ///   alphabets.  However, because at this time, the UTF-8 portion of the PKWare
        ///   specification is not broadly supported by other zip libraries and
        ///   utilities, such zip files may not be readable by your favorite zip tool or
        ///   archiver. In other words, interoperability will decrease if you set this
        ///   flag to true.
        /// </para>
        ///
        /// <para>
        ///   In particular, Zip files created with strict adherence to the PKWare
        ///   specification with respect to UTF-8 encoding will not work well with
        ///   Explorer in Windows XP or Windows Vista, because Windows compressed
        ///   folders, as far as I know, do not support UTF-8 in zip files.  Vista can
        ///   read the zip files, but shows the filenames incorrectly. Unpacking from
        ///   Windows Vista Explorer will result in filenames that have rubbish
        ///   characters in place of the high-order UTF-8 bytes.
        /// </para>
        ///
        /// <para>
        ///   Also, zip files that use UTF-8 encoding will not work well with Java
        ///   applications that use the java.util.zip classes, as of v5.0 of the Java
        ///   runtime. The Java runtime does not correctly implement the PKWare
        ///   specification in this regard.
        /// </para>
        ///
        /// <para>
        ///   As a result, we have the unfortunate situation that "correct" behavior by
        ///   the DotNetZip library with regard to Unicode encoding of filenames during
        ///   zip creation will result in zip files that are readable by strictly
        ///   compliant and current tools (for example the most recent release of the
        ///   commercial WinZip tool); but these zip files will not be readable by
        ///   various other tools or libraries, including Windows Explorer.
        /// </para>
        ///
        /// <para>
        ///   The DotNetZip library can read and write zip files with UTF8-encoded
        ///   entries, according to the PKware spec.  If you use DotNetZip for both
        ///   creating and reading the zip file, and you use UTF-8, there will be no
        ///   loss of information in the filenames. For example, using a self-extractor
        ///   created by this library will allow you to unpack files correctly with no
        ///   loss of information in the filenames.
        /// </para>
        ///
        /// <para>
        ///   If you do not set this flag, it will remain false.  If this flag is false,
        ///   the <c>ZipOutputStream</c> will encode all filenames and comments using
        ///   the IBM437 codepage.  This can cause "loss of information" on some
        ///   filenames, but the resulting zipfile will be more interoperable with other
        ///   utilities. As an example of the loss of information, diacritics can be
        ///   lost.  The o-tilde character will be down-coded to plain o.  The c with a
        ///   cedilla (Unicode 0xE7) used in Portugese will be downcoded to a c.
        ///   Likewise, the O-stroke character (Unicode 248), used in Danish and
        ///   Norwegian, will be down-coded to plain o. Chinese characters cannot be
        ///   represented in codepage IBM437; when using the default encoding, Chinese
        ///   characters in filenames will be represented as ?. These are all examples
        ///   of "information loss".
        /// </para>
        ///
        /// <para>
        ///   The loss of information associated to the use of the IBM437 encoding is
        ///   inconvenient, and can also lead to runtime errors. For example, using
        ///   IBM437, any sequence of 4 Chinese characters will be encoded as ????.  If
        ///   your application creates a <c>ZipOutputStream</c>, does not set the
        ///   encoding, then adds two files, each with names of four Chinese characters
        ///   each, this will result in a duplicate filename exception.  In the case
        ///   where you add a single file with a name containing four Chinese
        ///   characters, the zipfile will save properly, but extracting that file
        ///   later, with any zip tool, will result in an error, because the question
        ///   mark is not legal for use within filenames on Windows.  These are just a
        ///   few examples of the problems associated to loss of information.
        /// </para>
        ///
        /// <para>
        ///   This flag is independent of the encoding of the content within the entries
        ///   in the zip file. Think of the zip file as a container - it supports an
        ///   encoding.  Within the container are other "containers" - the file entries
        ///   themselves.  The encoding within those entries is independent of the
        ///   encoding of the zip archive container for those entries.
        /// </para>
        ///
        /// <para>
        ///   Rather than specify the encoding in a binary fashion using this flag, an
        ///   application can specify an arbitrary encoding via the <see
        ///   cref="ProvisionalAlternateEncoding"/> property.  Setting the encoding
        ///   explicitly when creating zip archives will result in non-compliant zip
        ///   files that, curiously, are fairly interoperable.  The challenge is, the
        ///   PKWare specification does not provide for a way to specify that an entry
        ///   in a zip archive uses a code page that is neither IBM437 nor UTF-8.
        ///   Therefore if you set the encoding explicitly when creating a zip archive,
        ///   you must take care upon reading the zip archive to use the same code page.
        ///   If you get it wrong, the behavior is undefined and may result in incorrect
        ///   filenames, exceptions, stomach upset, hair loss, and acne.
        /// </para>
        /// </remarks>
        /// <seealso cref="ProvisionalAlternateEncoding"/>
        [Obsolete("Beginning with v1.9.1.6 of DotNetZip, this property is obsolete. It will be removed in a future version of the library. Use AlternateEncoding and AlternateEncodingUsage instead.")]
        public bool UseUnicodeAsNecessary
        {
            get
            {
                return (_alternateEncoding == System.Text.Encoding.UTF8) &&
                    (AlternateEncodingUsage == ZipOption.AsNecessary);
            }
            set
            {
                if (value)
                {
                    _alternateEncoding = System.Text.Encoding.UTF8;
                    _alternateEncodingUsage = ZipOption.AsNecessary;

                }
                else
                {
                    _alternateEncoding = Ionic.Zip.ZipOutputStream.DefaultEncoding;
                    _alternateEncodingUsage = ZipOption.Never;
                }
            }
        }


        /// <summary>
        ///   The text encoding to use when emitting entries into the zip archive, for
        ///   those entries whose filenames or comments cannot be encoded with the
        ///   default (IBM437) encoding.
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   In <see href="http://www.pkware.com/documents/casestudies/APPNOTE.TXT">its
        ///   zip specification</see>, PKWare describes two options for encoding
        ///   filenames and comments: using IBM437 or UTF-8.  But, some archiving tools
        ///   or libraries do not follow the specification, and instead encode
        ///   characters using the system default code page.  For example, WinRAR when
        ///   run on a machine in Shanghai may encode filenames with the Big-5 Chinese
        ///   (950) code page.  This behavior is contrary to the Zip specification, but
        ///   it occurs anyway.
        /// </para>
        ///
        /// <para>
        ///   When using DotNetZip to write zip archives that will be read by one of
        ///   these other archivers, set this property to specify the code page to use
        ///   when encoding the <see cref="ZipEntry.FileName"/> and <see
        ///   cref="ZipEntry.Comment"/> for each <c>ZipEntry</c> in the zip file, for
        ///   values that cannot be encoded with the default codepage for zip files,
        ///   IBM437.  This is why this property is "provisional".  In all cases, IBM437
        ///   is used where possible, in other words, where no loss of data would
        ///   result. It is possible, therefore, to have a given entry with a
        ///   <c>Comment</c> encoded in IBM437 and a <c>FileName</c> encoded with the
        ///   specified "provisional" codepage.
        /// </para>
        ///
        /// <para>
        ///   Be aware that a zip file created after you've explicitly set the
        ///   <c>ProvisionalAlternateEncoding</c> property to a value other than
        ///   IBM437 may not be compliant to the PKWare specification, and may not be
        ///   readable by compliant archivers.  On the other hand, many (most?)
        ///   archivers are non-compliant and can read zip files created in arbitrary
        ///   code pages.  The trick is to use or specify the proper codepage when
        ///   reading the zip.
        /// </para>
        ///
        /// <para>
        ///   When creating a zip archive using this library, it is possible to change
        ///   the value of <c>ProvisionalAlternateEncoding</c> between each entry you
        ///   add, and between adding entries and the call to <c>Close()</c>. Don't do
        ///   this. It will likely result in a zipfile that is not readable.  For best
        ///   interoperability, either leave <c>ProvisionalAlternateEncoding</c>
        ///   alone, or specify it only once, before adding any entries to the
        ///   <c>ZipOutputStream</c> instance.  There is one exception to this
        ///   recommendation, described later.
        /// </para>
        ///
        /// <para>
        ///   When using an arbitrary, non-UTF8 code page for encoding, there is no
        ///   standard way for the creator application - whether DotNetZip, WinZip,
        ///   WinRar, or something else - to formally specify in the zip file which
        ///   codepage has been used for the entries. As a result, readers of zip files
        ///   are not able to inspect the zip file and determine the codepage that was
        ///   used for the entries contained within it.  It is left to the application
        ///   or user to determine the necessary codepage when reading zip files encoded
        ///   this way.  If you use an incorrect codepage when reading a zipfile, you
        ///   will get entries with filenames that are incorrect, and the incorrect
        ///   filenames may even contain characters that are not legal for use within
        ///   filenames in Windows. Extracting entries with illegal characters in the
        ///   filenames will lead to exceptions. It's too bad, but this is just the way
        ///   things are with code pages in zip files. Caveat Emptor.
        /// </para>
        ///
        /// <para>
        ///   One possible approach for specifying the code page for a given zip file is
        ///   to describe the code page in a human-readable form in the Zip comment. For
        ///   example, the comment may read "Entries in this archive are encoded in the
        ///   Big5 code page".  For maximum interoperability, the zip comment in this
        ///   case should be encoded in the default, IBM437 code page.  In this case,
        ///   the zip comment is encoded using a different page than the filenames.  To
        ///   do this, Specify <c>ProvisionalAlternateEncoding</c> to your desired
        ///   region-specific code page, once before adding any entries, and then set
        ///   the <see cref="Comment"/> property and reset
        ///   <c>ProvisionalAlternateEncoding</c> to IBM437 before calling <c>Close()</c>.
        /// </para>
        /// </remarks>
        [Obsolete("use AlternateEncoding and AlternateEncodingUsage instead.")]
        public System.Text.Encoding ProvisionalAlternateEncoding
        {
            get
            {
                if (_alternateEncodingUsage == ZipOption.AsNecessary)
                    return _alternateEncoding;
                return null;
            }
            set
            {
                _alternateEncoding = value;
                _alternateEncodingUsage = ZipOption.AsNecessary;
            }
        }

        /// <summary>
        ///   A Text Encoding to use when encoding the filenames and comments for
        ///   all the ZipEntry items, during a ZipFile.Save() operation.
        /// </summary>
        /// <remarks>
        ///   <para>
        ///     Whether the encoding specified here is used during the save depends
        ///     on <see cref="AlternateEncodingUsage"/>.
        ///   </para>
        /// </remarks>
        public System.Text.Encoding AlternateEncoding
        {
            get
            {
                return _alternateEncoding;
            }
            set
            {
                _alternateEncoding = value;
            }
        }

        /// <summary>
        ///   A flag that tells if and when this instance should apply
        ///   AlternateEncoding to encode the filenames and comments associated to
        ///   of ZipEntry objects contained within this instance.
        /// </summary>
        public ZipOption AlternateEncodingUsage
        {
            get
            {
                return _alternateEncodingUsage;
            }
            set
            {
                _alternateEncodingUsage = value;
            }
        }

        /// <summary>
        /// The default text encoding used in zip archives.  It is numeric 437, also
        /// known as IBM437.
        /// </summary>
        /// <seealso cref="Ionic.Zip.ZipFile.ProvisionalAlternateEncoding"/>
        public static System.Text.Encoding DefaultEncoding
        {
            get
            {
                return System.Text.Encoding.GetEncoding("IBM437");
            }
        }


#if !NETCF
        /// <summary>
        ///   The size threshold for an entry, above which a parallel deflate is used.
        /// </summary>
        ///
        /// <remarks>
        ///
        ///   <para>
        ///     DotNetZip will use multiple threads to compress any ZipEntry, when
        ///     the <c>CompressionMethod</c> is Deflate, and if the entry is
        ///     larger than the given size.  Zero means "always use parallel
        ///     deflate", while -1 means "never use parallel deflate".
        ///   </para>
        ///
        ///   <para>
        ///     If the entry size cannot be known before compression, as with any entry
        ///     added via a ZipOutputStream, then Parallel deflate will never be
        ///     performed, unless the value of this property is zero.
        ///   </para>
        ///
        ///   <para>
        ///     A parallel deflate operations will speed up the compression of
        ///     large files, on computers with multiple CPUs or multiple CPU
        ///     cores.  For files above 1mb, on a dual core or dual-cpu (2p)
        ///     machine, the time required to compress the file can be 70% of the
        ///     single-threaded deflate.  For very large files on 4p machines the
        ///     compression can be done in 30% of the normal time.  The downside
        ///     is that parallel deflate consumes extra memory during the deflate,
        ///     and the deflation is slightly less effective.
        ///   </para>
        ///
        ///   <para>
        ///     Parallel deflate tends to not be as effective as single-threaded deflate
        ///     because the original data stream is split into multiple independent
        ///     buffers, each of which is compressed in parallel.  But because they are
        ///     treated independently, there is no opportunity to share compression
        ///     dictionaries, and additional framing bytes must be added to the output
        ///     stream.  For that reason, a deflated stream may be slightly larger when
        ///     compressed using parallel deflate, as compared to a traditional
        ///     single-threaded deflate. For files of about 512k, the increase over the
        ///     normal deflate is as much as 5% of the total compressed size. For larger
        ///     files, the difference can be as small as 0.1%.
        ///   </para>
        ///
        ///   <para>
        ///     Multi-threaded compression does not give as much an advantage when using
        ///     Encryption. This is primarily because encryption tends to slow down
        ///     the entire pipeline. Also, multi-threaded compression gives less of an
        ///     advantage when using lower compression levels, for example <see
        ///     cref="Ionic.Zlib.CompressionLevel.BestSpeed"/>.  You may have to perform
        ///     some tests to determine the best approach for your situation.
        ///   </para>
        ///
        ///   <para>
        ///     The default value for this property is -1, which means parallel
        ///     compression will not be performed unless you set it to zero.
        ///   </para>
        ///
        /// </remarks>
        public long ParallelDeflateThreshold
        {
            set
            {
                if ((value != 0) && (value != -1) && (value < 64 * 1024))
                    throw new ArgumentOutOfRangeException("value must be greater than 64k, or 0, or -1");
                _ParallelDeflateThreshold = value;
            }
            get
            {
                return _ParallelDeflateThreshold;
            }
        }


        /// <summary>
        ///   The maximum number of buffer pairs to use when performing
        ///   parallel compression.
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   This property sets an upper limit on the number of memory
        ///   buffer pairs to create when performing parallel
        ///   compression.  The implementation of the parallel
        ///   compression stream allocates multiple buffers to
        ///   facilitate parallel compression.  As each buffer fills up,
        ///   the stream uses <see
        ///   cref="System.Threading.ThreadPool.QueueUserWorkItem(WaitCallback)">
        ///   ThreadPool.QueueUserWorkItem()</see> to compress those
        ///   buffers in a background threadpool thread. After a buffer
        ///   is compressed, it is re-ordered and written to the output
        ///   stream.
        /// </para>
        ///
        /// <para>
        ///   A higher number of buffer pairs enables a higher degree of
        ///   parallelism, which tends to increase the speed of compression on
        ///   multi-cpu computers.  On the other hand, a higher number of buffer
        ///   pairs also implies a larger memory consumption, more active worker
        ///   threads, and a higher cpu utilization for any compression. This
        ///   property enables the application to limit its memory consumption and
        ///   CPU utilization behavior depending on requirements.
        /// </para>
        ///
        /// <para>
        ///   For each compression "task" that occurs in parallel, there are 2
        ///   buffers allocated: one for input and one for output.  This property
        ///   sets a limit for the number of pairs.  The total amount of storage
        ///   space allocated for buffering will then be (N*S*2), where N is the
        ///   number of buffer pairs, S is the size of each buffer (<see
        ///   cref="CodecBufferSize"/>).  By default, DotNetZip allocates 4 buffer
        ///   pairs per CPU core, so if your machine has 4 cores, and you retain
        ///   the default buffer size of 128k, then the
        ///   ParallelDeflateOutputStream will use 4 * 4 * 2 * 128kb of buffer
        ///   memory in total, or 4mb, in blocks of 128kb.  If you then set this
        ///   property to 8, then the number will be 8 * 2 * 128kb of buffer
        ///   memory, or 2mb.
        /// </para>
        ///
        /// <para>
        ///   CPU utilization will also go up with additional buffers, because a
        ///   larger number of buffer pairs allows a larger number of background
        ///   threads to compress in parallel. If you find that parallel
        ///   compression is consuming too much memory or CPU, you can adjust this
        ///   value downward.
        /// </para>
        ///
        /// <para>
        ///   The default value is 16. Different values may deliver better or
        ///   worse results, depending on your priorities and the dynamic
        ///   performance characteristics of your storage and compute resources.
        /// </para>
        ///
        /// <para>
        ///   This property is not the number of buffer pairs to use; it is an
        ///   upper limit. An illustration: Suppose you have an application that
        ///   uses the default value of this property (which is 16), and it runs
        ///   on a machine with 2 CPU cores. In that case, DotNetZip will allocate
        ///   4 buffer pairs per CPU core, for a total of 8 pairs.  The upper
        ///   limit specified by this property has no effect.
        /// </para>
        ///
        /// <para>
        ///   The application can set this value at any time, but it is
        ///   effective only if set before calling
        ///   <c>ZipOutputStream.Write()</c> for the first time.
        /// </para>
        /// </remarks>
        ///
        /// <seealso cref="ParallelDeflateThreshold"/>
        ///
        public int ParallelDeflateMaxBufferPairs
        {
            get
            {
                return _maxBufferPairs;
            }
            set
            {
                if (value < 4)
                    throw new ArgumentOutOfRangeException("ParallelDeflateMaxBufferPairs",
                                                "Value must be 4 or greater.");
                _maxBufferPairs = value;
            }
        }
#endif


        private void InsureUniqueEntry(ZipEntry ze1)
        {
            if (_entriesWritten.ContainsKey(ze1.FileName))
            {
                _exceptionPending = true;
                throw new ArgumentException(String.Format("The entry '{0}' already exists in the zip archive.", ze1.FileName));
            }
        }


        internal Stream OutputStream
        {
            get
            {
                return _outputStream;
            }
        }

        internal String Name
        {
            get
            {
                return _name;
            }
        }

        /// <summary>
        ///   Returns true if an entry by the given name has already been written
        ///   to the ZipOutputStream.
        /// </summary>
        ///
        /// <param name="name">
        ///   The name of the entry to scan for.
        /// </param>
        ///
        /// <returns>
        /// true if an entry by the given name has already been written.
        /// </returns>
        public bool ContainsEntry(string name)
        {
            return _entriesWritten.ContainsKey(SharedUtilities.NormalizePathForUseInZipFile(name));
        }


        /// <summary>
        ///   Write the data from the buffer to the stream.
        /// </summary>
        ///
        /// <remarks>
        ///   As the application writes data into this stream, the data may be
        ///   compressed and encrypted before being written out to the underlying
        ///   stream, depending on the settings of the <see cref="CompressionLevel"/>
        ///   and the <see cref="Encryption"/> properties.
        /// </remarks>
        ///
        /// <param name="buffer">The buffer holding data to write to the stream.</param>
        /// <param name="offset">the offset within that data array to find the first byte to write.</param>
        /// <param name="count">the number of bytes to write.</param>
        public override void Write(byte[] buffer, int offset, int count)
        {
            if (_disposed)
            {
                _exceptionPending = true;
                throw new System.InvalidOperationException("The stream has been closed.");
            }

            if (buffer==null)
            {
                _exceptionPending = true;
                throw new System.ArgumentNullException("buffer");
            }

            if (_currentEntry == null)
            {
                _exceptionPending = true;
                throw new System.InvalidOperationException("You must call PutNextEntry() before calling Write().");
            }

            if (_currentEntry.IsDirectory)
            {
                _exceptionPending = true;
                throw new System.InvalidOperationException("You cannot Write() data for an entry that is a directory.");
            }

            if (_needToWriteEntryHeader)
                _InitiateCurrentEntry(false);

            if (count != 0)
                _entryOutputStream.Write(buffer, offset, count);
        }



        /// <summary>
        ///   Specify the name of the next entry that will be written to the zip file.
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   Call this method just before calling <see cref="Write(byte[], int, int)"/>, to
        ///   specify the name of the entry that the next set of bytes written to
        ///   the <c>ZipOutputStream</c> belongs to. All subsequent calls to <c>Write</c>,
        ///   until the next call to <c>PutNextEntry</c>,
        ///   will be inserted into the named entry in the zip file.
        /// </para>
        ///
        /// <para>
        ///   If the <paramref name="entryName"/> used in <c>PutNextEntry()</c> ends in
        ///   a slash, then the entry added is marked as a directory. Because directory
        ///   entries do not contain data, a call to <c>Write()</c>, before an
        ///   intervening additional call to <c>PutNextEntry()</c>, will throw an
        ///   exception.
        /// </para>
        ///
        /// <para>
        ///   If you don't call <c>Write()</c> between two calls to
        ///   <c>PutNextEntry()</c>, the first entry is inserted into the zip file as a
        ///   file of zero size.  This may be what you want.
        /// </para>
        ///
        /// <para>
        ///   Because <c>PutNextEntry()</c> closes out the prior entry, if any, this
        ///   method may throw if there is a problem with the prior entry.
        /// </para>
        ///
        /// <para>
        ///   This method returns the <c>ZipEntry</c>.  You can modify public properties
        ///   on the <c>ZipEntry</c>, such as <see cref="ZipEntry.Encryption"/>, <see
        ///   cref="ZipEntry.Password"/>, and so on, until the first call to
        ///   <c>ZipOutputStream.Write()</c>, or until the next call to
        ///   <c>PutNextEntry()</c>.  If you modify the <c>ZipEntry</c> <em>after</em>
        ///   having called <c>Write()</c>, you may get a runtime exception, or you may
        ///   silently get an invalid zip archive.
        /// </para>
        ///
        /// </remarks>
        ///
        /// <example>
        ///
        ///   This example shows how to create a zip file, using the
        ///   <c>ZipOutputStream</c> class.
        ///
        /// <code>
        /// private void Zipup()
        /// {
        ///     using (FileStream fs raw = File.Open(_outputFileName, FileMode.Create, FileAccess.ReadWrite ))
        ///     {
        ///         using (var output= new ZipOutputStream(fs))
        ///         {
        ///             output.Password = "VerySecret!";
        ///             output.Encryption = EncryptionAlgorithm.WinZipAes256;
        ///             output.PutNextEntry("entry1.txt");
        ///             byte[] buffer= System.Text.Encoding.ASCII.GetBytes("This is the content for entry #1.");
        ///             output.Write(buffer,0,buffer.Length);
        ///             output.PutNextEntry("entry2.txt");  // this will be zero length
        ///             output.PutNextEntry("entry3.txt");
        ///             buffer= System.Text.Encoding.ASCII.GetBytes("This is the content for entry #3.");
        ///             output.Write(buffer,0,buffer.Length);
        ///         }
        ///     }
        /// }
        /// </code>
        /// </example>
        ///
        /// <param name="entryName">
        ///   The name of the entry to be added, including any path to be used
        ///   within the zip file.
        /// </param>
        ///
        /// <returns>
        ///   The ZipEntry created.
        /// </returns>
        ///
        public ZipEntry PutNextEntry(String entryName)
        {
            if (String.IsNullOrEmpty(entryName))
                throw new ArgumentNullException("entryName");

            if (_disposed)
            {
                _exceptionPending = true;
                throw new System.InvalidOperationException("The stream has been closed.");
            }

            _FinishCurrentEntry();
            _currentEntry = ZipEntry.CreateForZipOutputStream(entryName);
            _currentEntry._container = new ZipContainer(this);
            _currentEntry._BitField |= 0x0008;  // workitem 8932
            _currentEntry.SetEntryTimes(DateTime.Now, DateTime.Now, DateTime.Now);
            _currentEntry.CompressionLevel = this.CompressionLevel;
            _currentEntry.CompressionMethod = this.CompressionMethod;
            _currentEntry.Password = _password; // workitem 13909
            _currentEntry.Encryption = this.Encryption;
            // workitem 12634
            _currentEntry.AlternateEncoding = this.AlternateEncoding;
            _currentEntry.AlternateEncodingUsage = this.AlternateEncodingUsage;

            if (entryName.EndsWith("/"))  _currentEntry.MarkAsDirectory();

            _currentEntry.EmitTimesInWindowsFormatWhenSaving = ((_timestamp & ZipEntryTimestamp.Windows) != 0);
            _currentEntry.EmitTimesInUnixFormatWhenSaving = ((_timestamp & ZipEntryTimestamp.Unix) != 0);
            InsureUniqueEntry(_currentEntry);
            _needToWriteEntryHeader = true;

            return _currentEntry;
        }



        private void _InitiateCurrentEntry(bool finishing)
        {
            // If finishing==true, this means we're initiating the entry at the time of
            // Close() or PutNextEntry().  If this happens, it means no data was written
            // for the entry - Write() was never called.  (The usual case us to call
            // _InitiateCurrentEntry(bool) from within Write().)  If finishing==true,
            // the entry could be either a zero-byte file or a directory.

            _entriesWritten.Add(_currentEntry.FileName,_currentEntry);
            _entryCount++; // could use _entriesWritten.Count, but I don't want to incur
            // the cost.

            if (_entryCount > 65534 && _zip64 == Zip64Option.Never)
            {
                _exceptionPending = true;
                throw new System.InvalidOperationException("Too many entries. Consider setting ZipOutputStream.EnableZip64.");
            }

            // Write out the header.
            //
            // If finishing, and encryption is in use, then we don't want to emit the
            // normal encryption header.  Signal that with a cycle=99 to turn off
            // encryption for zero-byte entries or directories.
            //
            // If finishing, then we know the stream length is zero.  Else, unknown
            // stream length.  Passing stream length == 0 allows an optimization so as
            // not to setup an encryption or deflation stream, when stream length is
            // zero.

            _currentEntry.WriteHeader(_outputStream, finishing ? 99 : 0);
            _currentEntry.StoreRelativeOffset();

            if (!_currentEntry.IsDirectory)
            {
                _currentEntry.WriteSecurityMetadata(_outputStream);
                _currentEntry.PrepOutputStream(_outputStream,
                                               finishing ? 0 : -1,
                                               out _outputCounter,
                                               out _encryptor,
                                               out _deflater,
                                               out _entryOutputStream);
            }
            _needToWriteEntryHeader = false;
        }



        private void _FinishCurrentEntry()
        {
            if (_currentEntry != null)
            {
                if (_needToWriteEntryHeader)
                    _InitiateCurrentEntry(true); // an empty entry - no writes

                _currentEntry.FinishOutputStream(_outputStream, _outputCounter, _encryptor, _deflater, _entryOutputStream);
                _currentEntry.PostProcessOutput(_outputStream);
                // workitem 12964
                if (_currentEntry.OutputUsedZip64!=null)
                    _anyEntriesUsedZip64 |= _currentEntry.OutputUsedZip64.Value;

                // reset all the streams
                _outputCounter = null; _encryptor = _deflater = null; _entryOutputStream = null;
            }
        }



        /// <summary>
        /// Dispose the stream
        /// </summary>
        ///
        /// <remarks>
        /// <para>
        ///   This method writes the Zip Central directory, then closes the stream.  The
        ///   application must call Dispose() (or Close) in order to produce a valid zip file.
        /// </para>
        ///
        /// <para>
        ///   Typically the application will call <c>Dispose()</c> implicitly, via a <c>using</c>
        ///   statement in C#, or a <c>Using</c> statement in VB.
        /// </para>
        ///
        /// </remarks>
        ///
        /// <param name="disposing">set this to true, always.</param>
        protected override void Dispose(bool disposing)
        {
            if (_disposed) return;

            if (disposing) // not called from finalizer
            {
                // handle pending exceptions
                if (!_exceptionPending)
                {
                    _FinishCurrentEntry();
                    _directoryNeededZip64 = ZipOutput.WriteCentralDirectoryStructure(_outputStream,
                                                                                     _entriesWritten.Values,
                                                                                     1, // _numberOfSegmentsForMostRecentSave,
                                                                                     _zip64,
                                                                                     Comment,
                                                                                     new ZipContainer(this));
                    Stream wrappedStream = null;
                    CountingStream cs = _outputStream as CountingStream;
                    if (cs != null)
                    {
                        wrappedStream = cs.WrappedStream;
#if NETCF
                    cs.Close();
#else
                        cs.Dispose();
#endif
                    }
                    else
                    {
                        wrappedStream = _outputStream;
                    }

                    if (!_leaveUnderlyingStreamOpen)
                    {
#if NETCF
                    wrappedStream.Close();
#else
                        wrappedStream.Dispose();
#endif
                    }
                    _outputStream = null;
                }
            }
            _disposed = true;
        }



        /// <summary>
        /// Always returns false.
        /// </summary>
        public override bool CanRead { get { return false; } }

        /// <summary>
        /// Always returns false.
        /// </summary>
        public override bool CanSeek { get { return false; } }

        /// <summary>
        /// Always returns true.
        /// </summary>
        public override bool CanWrite { get { return true; } }

        /// <summary>
        /// Always returns a NotSupportedException.
        /// </summary>
        public override long Length { get { throw new NotSupportedException(); } }

        /// <summary>
        /// Setting this property always returns a NotSupportedException. Getting it
        /// returns the value of the Position on the underlying stream.
        /// </summary>
        public override long Position
        {
            get { return _outputStream.Position; }
            set { throw new NotSupportedException(); }
        }

        /// <summary>
        /// This is a no-op.
        /// </summary>
        public override void Flush() { }

        /// <summary>
        /// This method always throws a NotSupportedException.
        /// </summary>
        /// <param name="buffer">ignored</param>
        /// <param name="offset">ignored</param>
        /// <param name="count">ignored</param>
        /// <returns>nothing</returns>
        public override int Read(byte[] buffer, int offset, int count)
        {
            throw new NotSupportedException("Read");
        }

        /// <summary>
        /// This method always throws a NotSupportedException.
        /// </summary>
        /// <param name="offset">ignored</param>
        /// <param name="origin">ignored</param>
        /// <returns>nothing</returns>
        public override long Seek(long offset, SeekOrigin origin)
        {
            throw new NotSupportedException("Seek");
        }

        /// <summary>
        /// This method always throws a NotSupportedException.
        /// </summary>
        /// <param name="value">ignored</param>
        public override void SetLength(long value)
        {
            throw new NotSupportedException();
        }


        private EncryptionAlgorithm _encryption;
        private ZipEntryTimestamp _timestamp;
        internal String _password;
        private String _comment;
        private Stream _outputStream;
        private ZipEntry _currentEntry;
        internal Zip64Option _zip64;
        private Dictionary<String, ZipEntry> _entriesWritten;
        private int _entryCount;
        private ZipOption _alternateEncodingUsage = ZipOption.Never;
        private System.Text.Encoding _alternateEncoding
            = System.Text.Encoding.GetEncoding("IBM437"); // default = IBM437

        private bool _leaveUnderlyingStreamOpen;
        private bool _disposed;
        private bool _exceptionPending; // **see note below
        private bool _anyEntriesUsedZip64, _directoryNeededZip64;
        private CountingStream _outputCounter;
        private Stream _encryptor;
        private Stream _deflater;
        private Ionic.Crc.CrcCalculatorStream _entryOutputStream;
        private bool _needToWriteEntryHeader;
        private string _name;
        private bool _DontIgnoreCase;
#if !NETCF
        internal Ionic.Zlib.ParallelDeflateOutputStream ParallelDeflater;
        private long _ParallelDeflateThreshold;
        private int _maxBufferPairs = 16;
#endif

        // **Note regarding exceptions:

        // When ZipOutputStream is employed within a using clause, which
        // is the typical scenario, and an exception is thrown within
        // the scope of the using, Close()/Dispose() is invoked
        // implicitly before processing the initial exception.  In that
        // case, _exceptionPending is true, and we don't want to try to
        // write anything in the Close/Dispose logic.  Doing so can
        // cause additional exceptions that mask the original one. So,
        // the _exceptionPending flag is used to track that, and to
        // allow the original exception to be propagated to the
        // application without extra "noise."

    }



    internal class ZipContainer
    {
        private ZipFile _zf;
        private ZipOutputStream _zos;
        private ZipInputStream _zis;

        public ZipContainer(Object o)
        {
            _zf = (o as ZipFile);
            _zos = (o as ZipOutputStream);
            _zis = (o as ZipInputStream);
        }

        public ZipFile ZipFile
        {
            get { return _zf; }
        }

        public ZipOutputStream ZipOutputStream
        {
            get { return _zos; }
        }

        public string Name
        {
            get
            {
                if (_zf != null) return _zf.Name;
                if (_zis != null) throw new NotSupportedException();
                return _zos.Name;
            }
        }

        public string Password
        {
            get
            {
                if (_zf != null) return _zf._Password;
                if (_zis != null) return _zis._Password;
                return _zos._password;
            }
        }

        public Zip64Option Zip64
        {
            get
            {
                if (_zf != null) return _zf._zip64;
                if (_zis != null) throw new NotSupportedException();
                return _zos._zip64;
            }
        }

        public int BufferSize
        {
            get
            {
                if (_zf != null) return _zf.BufferSize;
                if (_zis != null) throw new NotSupportedException();
                return 0;
            }
        }

#if !NETCF
        public Ionic.Zlib.ParallelDeflateOutputStream ParallelDeflater
        {
            get
            {
                if (_zf != null) return _zf.ParallelDeflater;
                if (_zis != null) return null;
                return _zos.ParallelDeflater;
            }
            set
            {
                if (_zf != null) _zf.ParallelDeflater = value;
                else if (_zos != null) _zos.ParallelDeflater = value;
            }
        }

        public long ParallelDeflateThreshold
        {
            get
            {
                if (_zf != null) return _zf.ParallelDeflateThreshold;
                return _zos.ParallelDeflateThreshold;
            }
        }
        public int ParallelDeflateMaxBufferPairs
        {
            get
            {
                if (_zf != null) return _zf.ParallelDeflateMaxBufferPairs;
                return _zos.ParallelDeflateMaxBufferPairs;
            }
        }
#endif

        public int CodecBufferSize
        {
            get
            {
                if (_zf != null) return _zf.CodecBufferSize;
                if (_zis != null) return _zis.CodecBufferSize;
                return _zos.CodecBufferSize;
            }
        }

        public Ionic.Zlib.CompressionStrategy Strategy
        {
            get
            {
                if (_zf != null) return _zf.Strategy;
                return _zos.Strategy;
            }
        }

        public Zip64Option UseZip64WhenSaving
        {
            get
            {
                if (_zf != null) return _zf.UseZip64WhenSaving;
                return _zos.EnableZip64;
            }
        }

        public System.Text.Encoding AlternateEncoding
        {
            get
            {
                if (_zf != null) return _zf.AlternateEncoding;
                if (_zos!=null) return _zos.AlternateEncoding;
                return null;
            }
        }
        public System.Text.Encoding DefaultEncoding
        {
            get
            {
                if (_zf != null) return ZipFile.DefaultEncoding;
                if (_zos!=null) return ZipOutputStream.DefaultEncoding;
                return null;
            }
        }
        public ZipOption AlternateEncodingUsage
        {
            get
            {
                if (_zf != null) return _zf.AlternateEncodingUsage;
                if (_zos!=null) return _zos.AlternateEncodingUsage;
                return ZipOption.Never; // n/a
            }
        }

        public Stream ReadStream
        {
            get
            {
                if (_zf != null) return _zf.ReadStream;
                return _zis.ReadStream;
            }
        }
    }

}