WebService 数据压缩

很长时间没有更新博客了
一直在忙这做项目，累啊，苦啊
现在刚好忙完了，赶紧看看兄弟姐妹们的博客，其中看了刚刚兄有关Web服务初探：用Demo学Web服务系列，使自己才更清楚的了解了WebService，Thx！
然而项目中有时数据大，所以在网上搜了个压缩数据的，特此贴出来，方便自己日后用到，也希望能给大家一些帮助，呵呵
CompressionExtension.cs：

using System;
using System.IO;
using System.Text ;
using System.Web.Services;
using System.Web.Services.Protocols ;
using ICSharpCode.SharpZipLib.Checksums;
using ICSharpCode.SharpZipLib.Zip;
using ICSharpCode.SharpZipLib.GZip;
using System.Xml ;

namespace BLL
{
    /**//// <summary>
    /// Summary description for ConpressionExtension.
    /// </summary>
    public class CompressionExtension : System.Web.Services.Protocols.SoapExtension
    {
        Stream oldStream;
        Stream newStream;
    

        public override object GetInitializer(LogicalMethodInfo methodInfo, SoapExtensionAttribute attribute) 
        {
            return attribute;
        }

        // Get the Type
        public override object GetInitializer(Type t) 
        {
            return typeof(CompressionExtension);
        }
    
        // Get the CompressionExtensionAttribute
        public override void Initialize(object initializer) 
        {
            CompressionExtensionAttribute attribute = (CompressionExtensionAttribute) initializer;

            return;
        }

        // Process the SOAP Message
        public override void ProcessMessage(SoapMessage message) 
        {
            // Check for the various SOAP Message Stages 
            switch (message.Stage) 
            {

                case SoapMessageStage.BeforeSerialize:
                    break;

                case SoapMessageStage.AfterSerialize:
                    // ZIP the contents of the SOAP Body after it has
                    // been serialized
                    Zip();
                    break;

                case SoapMessageStage.BeforeDeserialize:
                    // Unzip the contents of the SOAP Body before it is
                    // deserialized
                    Unzip();
                    break;

                case SoapMessageStage.AfterDeserialize:
                    break;

                default:
                    throw new Exception("invalid stage");
            }
        }

        // Gives us the ability to get hold of the RAW SOAP message
        public override Stream ChainStream( Stream stream ) 
        {
            oldStream = stream;
            newStream = new MemoryStream();
            return newStream;
        }

        // Utility method to copy streams
        void Copy(Stream from, Stream to) 
        {
            TextReader reader = new StreamReader(from);
            TextWriter writer = new StreamWriter(to);
            writer.WriteLine(reader.ReadToEnd());
            writer.Flush();
        }

    
        // Zip the SOAP Body
        private void Zip() 
        {
            newStream.Position = 0;
            // Zip the SOAP Body
            newStream = ZipSoap(newStream);
            // Copy the streams
            Copy(newStream, oldStream);
        }

        // The actual ZIP method
        private byte[] Zip(string stringToZip) 
        {
            byte[] inputByteArray = Encoding.UTF8.GetBytes(stringToZip);
            MemoryStream ms = new MemoryStream();

            // Check the #ziplib docs for more information
            ZipOutputStream zipOut = new ZipOutputStream( ms ) ;
            ZipEntry ZipEntry = new ZipEntry("ZippedFile");
            zipOut.PutNextEntry(ZipEntry);
            zipOut.SetLevel(9);
            zipOut.Write(inputByteArray, 0 , inputByteArray.Length ) ;     
            zipOut.Finish();
            zipOut.Close();

            // Return the zipped contents
            return ms.ToArray();
        }

        // Select and Zip the appropriate parts of the SOAP message
        public MemoryStream ZipSoap(Stream streamToZip) 
        {
            streamToZip.Position = 0;
            // Load a XML Reader
            XmlTextReader reader = new XmlTextReader(streamToZip);
            XmlDocument dom = new XmlDocument();
            dom.Load(reader);
            // Load a NamespaceManager to enable XPath selection
            XmlNamespaceManager nsmgr = new XmlNamespaceManager(dom.NameTable);
            nsmgr.AddNamespace("soap", "http://schemas.xmlsoap.org/soap/envelope/");
            XmlNode node = dom.SelectSingleNode("//soap:Body", nsmgr);
            // Select the contents within the method defined in the SOAP body
            node = node.FirstChild.FirstChild;
            // Check if there are any nodes selected
            while( node != null )
            {
                if( node.InnerXml.Length > 0 )
                {
                    // Zip the data
                    byte[] outData = Zip(node.InnerXml);
                    // Convert it to Base64 for transfer over the internet
                    node.InnerXml = Convert.ToBase64String(outData) ;
                }
                // Move to the next parameter
                node = node.NextSibling ;
            }
            MemoryStream ms = new MemoryStream();
            // Save the updated data
            dom.Save(ms);
            ms.Position = 0;
      
            return ms;
        }

        // Unzip the SOAP Body
        private void Unzip() 
        {
            MemoryStream unzipedStream = new MemoryStream();
        
            TextReader reader = new StreamReader(oldStream);
            TextWriter writer = new StreamWriter(unzipedStream);
            writer.WriteLine(reader.ReadToEnd());
            writer.Flush();
            // Unzip the SOAP Body
            unzipedStream = UnzipSoap(unzipedStream);
            // Copy the streams
            Copy(unzipedStream, newStream);
     
            newStream.Position = 0;
        }

        // Actual Unzip logic
        private byte[] Unzip(string stringToUnzip) 
        {
            // Decode the Base64 encoding
            byte[] inputByteArray = Convert.FromBase64String( stringToUnzip ) ;
            MemoryStream ms = new MemoryStream(inputByteArray) ;
            MemoryStream ret = new MemoryStream();

            // Refer to #ziplib documentation for more info on this
            ZipInputStream zipIn = new ZipInputStream(ms);
            ZipEntry theEntry = zipIn.GetNextEntry();
            Byte[] buffer = new Byte[2048] ;
            int size = 2048;
            while (true) 
            {
                size = zipIn.Read(buffer, 0, buffer.Length);
                if (size > 0) 
                {
                    ret.Write(buffer, 0, size);
                } 
                else 
                {
                    break;
                }
            }
            return ret.ToArray();
        }

        // Unzip the SOAP Body
        public MemoryStream UnzipSoap(Stream streamToUnzip) 
        {
            streamToUnzip.Position = 0;
            // Load a XmlReader
            XmlTextReader reader = new XmlTextReader(streamToUnzip);
            XmlDocument dom = new XmlDocument();
            dom.Load(reader);

            XmlNamespaceManager nsmgr = new XmlNamespaceManager(dom.NameTable);
            nsmgr.AddNamespace("soap", "http://schemas.xmlsoap.org/soap/envelope/");
            // Select the SOAP Body node 
            XmlNode node = dom.SelectSingleNode("//soap:Body", nsmgr);
            node = node.FirstChild.FirstChild;

            // Check if node exists
            while( node != null )
            {
                if( node.InnerXml.Length >0 )
                {
                    // Send the node's contents to be unziped
                    byte[] outData = Unzip(node.InnerXml);
                    string sTmp = Encoding.UTF8.GetString(outData);
                    node.InnerXml = sTmp;
                }
                // Move to the next parameter 
                node = node.NextSibling ;
            }

            MemoryStream ms = new MemoryStream();
      
            dom.Save(ms);
            ms.Position = 0;

            return ms;
        }

    }
}

CompressionExtensionAttribute.cs：

using System;
using System.Web.Services;
using System.Web.Services.Protocols;

namespace BLL
{

    /**//// <summary>
    /// Summary description for CompressionExtensionAttribute.
    /// </summary>
    
    // Make the Attribute only Applicable to Methods
    [AttributeUsage(AttributeTargets.Method)]
    public class CompressionExtensionAttribute : System.Web.Services.Protocols.SoapExtensionAttribute
    {
    
        private int priority;

        // Override the base class properties
        public override Type ExtensionType 
        {
            get { return typeof(CompressionExtension); }
        }

        public override int Priority 
        {
            get 
            { 
                return priority; 
            }
            set 
            { 
                priority = value; 
            }
        }

    }
}

在server | Client 都需要
调用很简单，只要在代理类中web方法加个：

[CompressionExtension]

原文地址：http://www.123aspx.com/redir.aspx?res=29459