gzip C#/.NET GZipHttpWebResponse.cs

Reference the needed namespaces.

using System;

using System.Web;

using System.IO;

using System.Net;

using System.Runtime.Serialization;

using System.Xml;

// #ZipLib was developed by Mike Krueger, and is available under the GNU Public License at:

//http://www.icsharpcode.net/OpenSource/SharpZipLib/Default.aspx

Specify the namespace for this class.

using ICSharpCode.SharpZipLib.GZip;

namespace Galileo.Web

{

/// <summary>

/// HttpWebResponse with gzip decompression

/// The source for this class is based on this article on dotnetjunkies.com:

///http://www.dotnetjunkies.com/Tutorial/46630AE2-1C79-4D5F-827E-6C2857FF1D23.dcik

/// </summary>

[Serializable]

Constructor. Take what we need from the response parameter, decompressing the response stream if it is compressed.

public class GZipHttpWebResponse : WebResponse

{

Declare member variables.

private Stream m_decompressedStream;

private string _contentType;

private long _contentLength;

private string _contentEncoding;

private Uri _responseUri;

private WebHeaderCollection _httpResponseHeaders;

///// <summary>

///// default constructor from WebResponse

///// </summary>

///// <param name="serializationInfo"></param>

///// <param name="streamingContext"></param>

//protected GZipHttpWebResponse(

//SerializationInfo serializationInfo,

//StreamingContext streamingContext

//) : base (serializationInfo, streamingContext)

//{

//}

//

Override base class behavior to use our member variables for these properties.

public override long ContentLength

{

set

{

_contentLength = value;

}

get

{

return _contentLength;

}

}

public override string ContentType

{

set

{

_contentType = value;

}

get

{

return _contentType;

}

}

public override WebHeaderCollection Headers

{

get

{

return _httpResponseHeaders;

}

}

public string ContentEncoding

{

set

{

_contentEncoding = value;;

}

get

{

return _contentEncoding;

}

}

public GZipHttpWebResponse(HttpWebResponse response)

{

try

{

Initialize our members variables from the HttpWebResponse object.

_contentType = response.ContentType;

_contentLength = response.ContentLength;

_contentEncoding = response.ContentEncoding;

_responseUri = response.ResponseUri;

_httpResponseHeaders = response.Headers;

If the response is compressed, then decompress it into a memory stream.

if (_contentEncoding=="gzip")

{

// Decompress response stream with GZip

const int BUF_SIZE = 16384;

Stream compressedStream = new GZipInputStream(response.GetResponseStream(), BUF_SIZE);

m_decompressedStream = new MemoryStream();

byte[] writeData = new byte[BUF_SIZE];

int size = compressedStream.Read(writeData, 0, BUF_SIZE);

while (size > 0)

{

m_decompressedStream.Write(writeData, 0, size);

size = compressedStream.Read(writeData, 0, BUF_SIZE);

}

m_decompressedStream.Seek(0, SeekOrigin.Begin);

_contentEncoding = "";

_httpResponseHeaders.Remove("Content-Encoding");

_contentLength = m_decompressedStream.Length;

// We have decompressed the entire response, so we no longer need the compressed version.

response.Close();

}

If the response is not compressed, just...

else

{

...return the response stream from the HttpWebResponse object.

m_decompressedStream = response.GetResponseStream();

}

}

If an exception occurs, clean up the resources we are using and re-throw the exception.

catch(Exception)

{

// We got an exception processing the response. Clean up.

response.Close();

Close();

throw;

}

}

Make sure to close the decompressed stream when the object is deleted.

~GZipHttpWebResponse()

{

Close();

}

Return the stream referenced by our local member variable.

public override Stream GetResponseStream()

{

return m_decompressedStream;

}

public override void Close()

{

If our member variable is pointing to a stream, close it.

if(m_decompressedStream != null)

{

m_decompressedStream.Close();

m_decompressedStream = null;

}

}

Override base class behavior to use our member variables for these properties.

public override Uri ResponseUri { get { return _responseUri; } }

}

}