我有一个具有以下配置的WCF服务：
<system.serviceModel>
<behaviors>
<serviceBehaviors>
<behavior name="MetadataEnabled">
<serviceDebug includeExceptionDetailInFaults="true" />
<serviceMetadata httpGetEnabled="true" />
</behavior>
</serviceBehaviors>
</behaviors>
<services>
<service behaviorConfiguration="MetadataEnabled" name="MyNamespace.MyService">
<endpoint name="BasicHttp"
address=""
binding="basicHttpBinding"
contract="MyNamespace.IMyServiceContract" />
<endpoint name="MetadataHttp"
address="contract"
binding="mexHttpBinding"
contract="IMetadataExchange" />
<host>
<baseAddresses>
<add baseAddress="http://localhost/myservice" />
</baseAddresses>
</host>
</service>
</services>
</system.serviceModel>
在wcfsvchost.exe进程中托管服务时，如果浏览到URL：
http://localhost/myservice/contract
在服务元数据可用的地方，我得到一个http 400错误请求错误。
通过检查wcf日志，我发现一个system.xml.xmlException异常被抛出，并显示消息：“消息正文为空，无法读取。”下面是日志文件的摘录：
<Exception>
<ExceptionType>
System.ServiceModel.ProtocolException, System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
</ExceptionType>
<Message>There is a problem with the XML that was received from the network. See inner exception for more details.</Message>
<StackTrace>
at System.ServiceModel.Channels.HttpRequestContext.CreateMessage()
at System.ServiceModel.Channels.HttpChannelListener.HttpContextReceived(HttpRequestContext context, ItemDequeuedCallback callback)
at System.ServiceModel.Channels.SharedHttpTransportManager.OnGetContextCore(IAsyncResult result)
at System.ServiceModel.Channels.SharedHttpTransportManager.OnGetContext(IAsyncResult result)
at System.ServiceModel.Diagnostics.Utility.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result)
at System.Net.LazyAsyncResult.Complete(IntPtr userToken)
at System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken)
at System.Net.ListenerAsyncResult.WaitCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped)
at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)
</StackTrace>
<InnerException>
<ExceptionType>System.Xml.XmlException, System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType>
<Message>The body of the message cannot be read because it is empty.</Message>
<StackTrace>
at System.ServiceModel.Channels.HttpRequestContext.CreateMessage()
at System.ServiceModel.Channels.HttpChannelListener.HttpContextReceived(HttpRequestContext context, ItemDequeuedCallback callback)
at System.ServiceModel.Channels.SharedHttpTransportManager.OnGetContextCore(IAsyncResult result)
at System.ServiceModel.Channels.SharedHttpTransportManager.OnGetContext(IAsyncResult result)
at System.ServiceModel.Diagnostics.Utility.AsyncThunk.UnhandledExceptionFrame(IAsyncResult result)
at System.Net.LazyAsyncResult.Complete(IntPtr userToken)
at System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken)
at System.Net.ListenerAsyncResult.WaitCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped)
at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)
</StackTrace>
</InnerException>
</Exception>
如果我改为浏览到URL：
http://localhost/myservice?wsdl
一切正常，我得到了wsdl合同。在这一点上，我还可以完全删除“metadatahttp”元数据端点，这不会有任何区别。
我正在使用.NET3.5SP1。有人知道这里可能出什么问题吗？
最佳答案
我想我找到了问题所在。
如果我浏览到URL：
http://localhost/myservice/contract
使用wcftestclient应用程序，我可以成功检索服务元数据。
所以这个错误只有在我通过web浏览器请求url时才会发生。
HTTP错误请求错误是因为浏览器发出了一个HTTP GET请求，其中消息的内容在HTTP头中，而正文是空的。这正是WCF MexHttpBinding所抱怨的！
为了通过Web浏览器获取服务契约，您必须在服务行为中显式启用它：
<serviceBehaviors>
<behavior name="MetadataEnabled">
<serviceMetadata httpGetEnabled="true" />
</behavior>
</serviceBehaviors>
请求的url变为：
http://localhost/myservice?wsdl
所以，结果我发这个问题有点太快了。不过，我还是会保留下来，只是为了记录。
关于wcf - 请求WCF服务契约(Contract)时出现HTTP错误请求错误，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/323551/