原文:
通过抓包知道WCF在提交、返回数据的时候大多使用XML进行数据交互，如果返回DataTable那么这些数据将变得很大，通过查询找到一个对数据压缩的方法：
新增项目GZipEncoder，GzipEncoder中增加三个文件 ：
GZipMessageEncoderFactory.cs
using System;using System.Collections.Generic;using System.Configuration;using System.Text;using System.IO;using System.IO.Compression;using System.Runtime.Serialization;using System.Runtime.InteropServices;using System.Security;using System.ServiceModel;using System.ServiceModel.Channels;using System.ServiceModel.Configuration;using System.Xml;using System.ServiceModel.Security;using System.ServiceModel.Description;namespace GZipEncoder{ //This class is used to create the custom encoder (GZipMessageEncoder) internal class GZipMessageEncoderFactory : MessageEncoderFactory { MessageEncoder encoder; //The GZip encoder wraps an inner encoder //We require a factory to be passed in that will create this inner encoder public GZipMessageEncoderFactory(MessageEncoderFactory messageEncoderFactory) { if (messageEncoderFactory == null) throw new ArgumentNullException("messageEncoderFactory", "A valid message encoder factory must be passed to the GZipEncoder"); encoder = new GZipMessageEncoder(messageEncoderFactory.Encoder); } //The service framework uses this property to obtain an encoder from this encoder factory public override MessageEncoder Encoder { get { return encoder; } } public override MessageVersion MessageVersion { get { return encoder.MessageVersion; } } //This is the actual GZip encoder class GZipMessageEncoder : MessageEncoder { static string GZipContentType = "application/x-gzip"; //This implementation wraps an inner encoder that actually converts a WCF Message //into textual XML, binary XML or some other format. This implementation then compresses the results. //The opposite happens when reading messages. //This member stores this inner encoder. MessageEncoder innerEncoder; //We require an inner encoder to be supplied (see comment above) internal GZipMessageEncoder(MessageEncoder messageEncoder) : base() { if (messageEncoder == null) throw new ArgumentNullException("messageEncoder", "A valid message encoder must be passed to the GZipEncoder"); innerEncoder = messageEncoder; } //public override string CharSet //{ // get { return ""; } //} public override string ContentType { get { return GZipContentType; } } public override string MediaType { get { return GZipContentType; } } //SOAP version to use - we delegate to the inner encoder for this public override MessageVersion MessageVersion { get { return innerEncoder.MessageVersion; } } //Helper method to compress an array of bytes static ArraySegment CompressBuffer(ArraySegment buffer, BufferManager bufferManager, int messageOffset) { MemoryStream memoryStream = new MemoryStream(); memoryStream.Write(buffer.Array, 0, messageOffset); using (GZipStream gzStream = new GZipStream(memoryStream, CompressionMode.Compress, true)) { gzStream.Write(buffer.Array, messageOffset, buffer.Count); } byte[] compressedBytes = memoryStream.ToArray(); byte[] bufferedBytes = bufferManager.TakeBuffer(compressedBytes.Length); Array.Copy(compressedBytes, 0, bufferedBytes, 0, compressedBytes.Length); bufferManager.ReturnBuffer(buffer.Array); ArraySegment byteArray = new ArraySegment (bufferedBytes, messageOffset, bufferedBytes.Length - messageOffset); return byteArray; } //Helper method to decompress an array of bytes static ArraySegment DecompressBuffer(ArraySegment buffer, BufferManager bufferManager) { MemoryStream memoryStream = new MemoryStream(buffer.Array, buffer.Offset, buffer.Count - buffer.Offset); MemoryStream decompressedStream = new MemoryStream(); int totalRead = 0; int blockSize = 1024; byte[] tempBuffer = bufferManager.TakeBuffer(blockSize); using (GZipStream gzStream = new GZipStream(memoryStream, CompressionMode.Decompress)) { while (true) { int bytesRead = gzStream.Read(tempBuffer, 0, blockSize); if (bytesRead == 0) break; decompressedStream.Write(tempBuffer, 0, bytesRead); totalRead += bytesRead; } } bufferManager.ReturnBuffer(tempBuffer); byte[] decompressedBytes = decompressedStream.ToArray(); byte[] bufferManagerBuffer = bufferManager.TakeBuffer(decompressedBytes.Length + buffer.Offset); Array.Copy(buffer.Array, 0, bufferManagerBuffer, 0, buffer.Offset); Array.Copy(decompressedBytes, 0, bufferManagerBuffer, buffer.Offset, decompressedBytes.Length); ArraySegment byteArray = new ArraySegment (bufferManagerBuffer, buffer.Offset, decompressedBytes.Length); bufferManager.ReturnBuffer(buffer.Array); return byteArray; } //One of the two main entry points into the encoder. Called by WCF to decode a buffered byte array into a Message. public override Message ReadMessage(ArraySegment buffer, BufferManager bufferManager, string contentType) { //Decompress the buffer ArraySegment decompressedBuffer = DecompressBuffer(buffer, bufferManager); //Use the inner encoder to decode the decompressed buffer Message returnMessage = innerEncoder.ReadMessage(decompressedBuffer, bufferManager); returnMessage.Properties.Encoder = this; return returnMessage; } //One of the two main entry points into the encoder. Called by WCF to encode a Message into a buffered byte array. public override ArraySegment WriteMessage(Message message, int maxMessageSize, BufferManager bufferManager, int messageOffset) { //Use the inner encoder to encode a Message into a buffered byte array ArraySegment buffer = innerEncoder.WriteMessage(message, maxMessageSize, bufferManager, messageOffset); //Compress the resulting byte array return CompressBuffer(buffer, bufferManager, messageOffset); } public override Message ReadMessage(System.IO.Stream stream, int maxSizeOfHeaders, string contentType) { GZipStream gzStream = new GZipStream(stream, CompressionMode.Decompress, true); return innerEncoder.ReadMessage(gzStream, maxSizeOfHeaders); } public override void WriteMessage(Message message, System.IO.Stream stream) { using (GZipStream gzStream = new GZipStream(stream, CompressionMode.Compress, true)) { innerEncoder.WriteMessage(message, gzStream); } // innerEncoder.WriteMessage(message, gzStream) depends on that it can flush data by flushing // the stream passed in, but the implementation of GZipStream.Flush will not flush underlying // stream, so we need to flush here. stream.Flush(); } } }} GZipMessageEncodingBindingElement.cs
using System;using System.Xml;using System.ServiceModel;using System.Configuration;using System.ServiceModel.Channels;using System.ServiceModel.Configuration;using System.ServiceModel.Description;namespace GZipEncoder{ // This is constants for GZip message encoding policy. static class GZipMessageEncodingPolicyConstants { public const string GZipEncodingName = "GZipEncoding"; public const string GZipEncodingNamespace = "http://schemas.microsoft.com/ws/06/2004/mspolicy/netgzip1"; public const string GZipEncodingPrefix = "gzip"; } //This is the binding element that, when plugged into a custom binding, will enable the GZip encoder public sealed class GZipMessageEncodingBindingElement : MessageEncodingBindingElement //BindingElement , IPolicyExportExtension { //We will use an inner binding element to store information required for the inner encoder MessageEncodingBindingElement innerBindingElement; //By default, use the default text encoder as the inner encoder public GZipMessageEncodingBindingElement() : this(new TextMessageEncodingBindingElement()) { } public GZipMessageEncodingBindingElement(MessageEncodingBindingElement messageEncoderBindingElement) { this.innerBindingElement = messageEncoderBindingElement; } public MessageEncodingBindingElement InnerMessageEncodingBindingElement { get { return innerBindingElement; } set { innerBindingElement = value; } } //Main entry point into the encoder binding element. Called by WCF to get the factory that will create the //message encoder public override MessageEncoderFactory CreateMessageEncoderFactory() { return new GZipMessageEncoderFactory(innerBindingElement.CreateMessageEncoderFactory()); } public override MessageVersion MessageVersion { get { return innerBindingElement.MessageVersion; } set { innerBindingElement.MessageVersion = value; } } public override BindingElement Clone() { return new GZipMessageEncodingBindingElement(this.innerBindingElement); } public override T GetProperty (BindingContext context) { if (typeof(T) == typeof(XmlDictionaryReaderQuotas)) { return innerBindingElement.GetProperty (context); } else { return base.GetProperty (context); } } public override IChannelFactory BuildChannelFactory (BindingContext context) { if (context == null) throw new ArgumentNullException("context"); context.BindingParameters.Add(this); return context.BuildInnerChannelFactory (); } public override IChannelListener BuildChannelListener (BindingContext context) { if (context == null) throw new ArgumentNullException("context"); context.BindingParameters.Add(this); return context.BuildInnerChannelListener (); } public override bool CanBuildChannelListener (BindingContext context) { if (context == null) throw new ArgumentNullException("context"); context.BindingParameters.Add(this); return context.CanBuildInnerChannelListener (); } void IPolicyExportExtension.ExportPolicy(MetadataExporter exporter, PolicyConversionContext policyContext) { if (policyContext == null) { throw new ArgumentNullException("policyContext"); } XmlDocument document = new XmlDocument(); policyContext.GetBindingAssertions().Add(document.CreateElement( GZipMessageEncodingPolicyConstants.GZipEncodingPrefix, GZipMessageEncodingPolicyConstants.GZipEncodingName, GZipMessageEncodingPolicyConstants.GZipEncodingNamespace)); } } //This class is necessary to be able to plug in the GZip encoder binding element through //a configuration file public class GZipMessageEncodingElement : BindingElementExtensionElement { public GZipMessageEncodingElement() { } //Called by the WCF to discover the type of binding element this config section enables public override Type BindingElementType { get { return typeof(GZipMessageEncodingBindingElement); } } //The only property we need to configure for our binding element is the type of //inner encoder to use. Here, we support text and binary. [ConfigurationProperty("innerMessageEncoding", DefaultValue = "textMessageEncoding")] public string InnerMessageEncoding { get { return (string)base["innerMessageEncoding"]; } set { base["innerMessageEncoding"] = value; } } //Called by the WCF to apply the configuration settings (the property above) to the binding element public override void ApplyConfiguration(BindingElement bindingElement) { GZipMessageEncodingBindingElement binding = (GZipMessageEncodingBindingElement)bindingElement; PropertyInformationCollection propertyInfo = this.ElementInformation.Properties; if (propertyInfo["innerMessageEncoding"].ValueOrigin != PropertyValueOrigin.Default) { switch (this.InnerMessageEncoding) { case "textMessageEncoding": binding.InnerMessageEncodingBindingElement = new TextMessageEncodingBindingElement(); break; case "binaryMessageEncoding": binding.InnerMessageEncodingBindingElement = new BinaryMessageEncodingBindingElement(); break; } } } //Called by the WCF to create the binding element protected override BindingElement CreateBindingElement() { GZipMessageEncodingBindingElement bindingElement = new GZipMessageEncodingBindingElement(); this.ApplyConfiguration(bindingElement); return bindingElement; } }} GZipMessageEncodingBindingElementImporter.cs
using System;using System.Xml;using System.ServiceModel.Description;using System.Xml.Schema;using System.Collections.ObjectModel;using System.Collections.Generic;using System.Text;namespace GZipEncoder{ public class GZipMessageEncodingBindingElementImporter : IPolicyImportExtension { public GZipMessageEncodingBindingElementImporter() { } void IPolicyImportExtension.ImportPolicy(MetadataImporter importer, PolicyConversionContext context) { if (importer == null) { throw new ArgumentNullException("importer"); } if (context == null) { throw new ArgumentNullException("context"); } ICollection assertions = context.GetBindingAssertions(); foreach (XmlElement assertion in assertions) { if ((assertion.NamespaceURI == GZipMessageEncodingPolicyConstants.GZipEncodingNamespace) && (assertion.LocalName == GZipMessageEncodingPolicyConstants.GZipEncodingName) ) { assertions.Remove(assertion); context.BindingElements.Add(new GZipMessageEncodingBindingElement()); break; } } } }} WCF Server 和 Client 都引用项目 GZipEncoder，然后修改config文件
Server web.config 中增加：
客户端的app.config 配置：
这样就完成了WCF的数据压缩，其他代码都不用动，直接可以使用
通过抓包看到Send和Recv的数据都为 application/x-gzip 格式
另外出现第一次调用WCF很慢的解决方法是将 useDefaultWebProxy 这个属性改成false，不让它找代理。这样就会在程序第一次调用WCF的时候快很多。
posted on 2015-07-10 09:59 阅读( ...) 评论( ...)