我正在尝试在。net中实现一个SoapExtension，它将压缩所有soap流量(请求和响应)。我可以控制客户端和服务器。我已经开始复制这个:http://www.mastercsharp.com/article.aspx?ArticleID=86&&TopicID=7并稍微修改它，我有一个问题。
当它从客户端发送时，我能够修改(zip)请求体，它到达服务器，反向操作(解压缩)也很好，但我似乎无法得到框架来反映我对流对象所做的更改!在服务器上，我将正确的数据设置为newStream对象，但是当调用WebMethod时，参数仍然被压缩(因此无效)。知道为什么吗?
为了让包括我自己在内的每个人都更容易，我将SoapExtension简化为:
using System;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.IO;
using System.Net;
// Define a SOAP Extension that traces the SOAP request and SOAP
// response for the XML Web service method the SOAP extension is
// applied to.
public class TraceExtension : SoapExtension {
Stream oldStream;
Stream newStream;
string filename;
// Save the Stream representing the SOAP request or SOAP response into
// a local memory buffer.
public override Stream ChainStream(Stream stream)
{
oldStream = stream;
newStream = new MemoryStream();
return newStream;
}
// When the SOAP extension is accessed for the first time, the XML Web
// service method it is applied to is accessed to store the file
// name passed in, using the corresponding SoapExtensionAttribute.
public override object GetInitializer(LogicalMethodInfo methodInfo, SoapExtensionAttribute attribute)
{
return ((TraceExtensionAttribute)attribute).Filename;
}
// The SOAP extension was configured to run using a configuration file
// instead of an attribute applied to a specific XML Web service
// method.
public override object GetInitializer(Type WebServiceType)
{
// Return a file name to log the trace information to, based on the
// type.
return "C:\" + WebServiceType.FullName + ".log";
}
// Receive the file name stored by GetInitializer and store it in a
// member variable for this specific instance.
public override void Initialize(object initializer)
{
filename = (string)initializer;
}
// If the SoapMessageStage is such that the SoapRequest or
// SoapResponse is still in the SOAP format to be sent or received,
// save it out to a file.
public override void ProcessMessage(SoapMessage message)
{
switch (message.Stage)
{
case SoapMessageStage.BeforeSerialize:
break;
case SoapMessageStage.AfterSerialize:
WriteOutput(message);
break;
case SoapMessageStage.BeforeDeserialize:
WriteInput(message);
break;
case SoapMessageStage.AfterDeserialize:
break;
}
}
public void WriteOutput(SoapMessage message)
{
newStream.Position = 0;
FileStream fs = new FileStream(filename, FileMode.Append,
FileAccess.Write);
StreamWriter w = new StreamWriter(fs);
string soapString = (message is SoapServerMessage) ? "SoapResponse" : "SoapRequest";
w.WriteLine("-----" + soapString + " at " + DateTime.Now);
w.Flush();
Copy(newStream, fs);
w.Close();
newStream.Position = 0;
Copy(newStream, oldStream);
}
//public void WriteInput(SoapMessage message)
//{
// Copy(oldStream, newStream);
// FileStream fs = new FileStream(filename, FileMode.Append,
// FileAccess.Write);
// StreamWriter w = new StreamWriter(fs);
// string soapString = (message is SoapServerMessage) ?
// "SoapRequest" : "SoapResponse";
// w.WriteLine("-----" + soapString +
// " at " + DateTime.Now);
// w.Flush();
// newStream.Position = 0;
// Copy(newStream, fs);
// w.Close();
// newStream.Position = 0;
//}
public void WriteInput(SoapMessage message)
{
oldStream.Position = 0;
StreamReader reader = new StreamReader(oldStream);
StreamWriter writer = new StreamWriter(newStream);
string data = reader.ReadToEnd();
data = data.Replace("false", "true");
writer.Write(data);
writer.Flush();
}
void Copy(Stream from, Stream to)
{
TextReader reader = new StreamReader(from);
TextWriter writer = new StreamWriter(to);
writer.WriteLine(reader.ReadToEnd());
writer.Flush();
}
}
它仍然不能正常工作。当服务器接收到soap请求(WriteInput方法)时，所有的"false"值都被更改为"true"，数据被保存到newStream对象中，但它仍然会在webmethod调用中显示"false"值!
我的调用是这样的:客户:
[SoapDocumentMethodAttribute("http://Company.com/Product/admintool/webservices/SaveNativeRequest", RequestNamespace = "http://Company.com/Product/admintool/webservices/", ResponseNamespace = "http://Company.com/Product/admintool/webservices/", Use = SoapBindingUse.Literal, ParameterStyle = SoapParameterStyle.Wrapped)]
[SoapHeaderAttribute("Ticket")]
[TraceExtension(Priority = 0)]
public void SaveNativeRequest(XmlNode nativeRequest, int? batchId)
{
this.Invoke("SaveNativeRequest", new object[] { nativeRequest, batchId });
}
[WebMethod]
[TraceExtension(Priority = 0)]
[SoapHeader("Ticket", Direction = SoapHeaderDirection.In)]
public void SaveNativeRequest(XmlNode nativeRequest, int? batchId)
{...}
为了完整，这是属性类
// Create a SoapExtensionAttribute for the SOAP Extension that can be
// applied to an XML Web service method.
using System;
using System.Web.Services.Protocols;
[AttributeUsage(AttributeTargets.Method)]
public class TraceExtensionAttribute : SoapExtensionAttribute
{
private string filename = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) + @"log.txt";
private int priority;
public override Type ExtensionType
{
get { return typeof(TraceExtension); }
}
public override int Priority
{
get { return priority; }
set { priority = value; }
}
public string Filename
{
get
{
return filename;
}
set
{
filename = value;
}
}
}
我已经看了这篇文章:h**p://hyperthink.net/blog/inside-of-chainstream/，我很确定我正确地使用了chainstream方法。我知道还有其他方法，但这似乎是最干净的选择。我读过关于这个主题的各种文章，这篇http://msdn.microsoft.com/en-us/magazine/cc188761.aspx文章启发了我一个解决方法，我可以使用
(System.Web.HttpContext.Current.Items["RequestSoapContext"] as Microsoft.Web.Services3.SoapContext).Envelope.Body
在ProcessMessage方法中直接操作soap体(这工作得很好，但是很难看)
我是否忽略了一些明显的东西?应用程序的其他部分是否会干扰服务器上的流链?如果有人对此有任何见解，我将非常非常高兴。
我认为你需要重置newStream在WriteInput方法中的位置。
所以请在WriteInput方法的末尾添加以下一行:
newStream.Position = 0;
应该能解决你的问题。