更改WCF System.ServiceModel.ClientBase的Endpoint.Binding不起作用

Question

我正在使用以编程方式配置的WCF客户端（System.ServiceModel.ClientBase）。此WCF客户端使用CustomBinding进行配置，默认情况下它具有TextMessageEncodingBindingElement。

现在，当我尝试切换到Mtom编码时，我更改了客户端的Endpoint.Binding属性，该属性工作正常。 Endpoint.Binding属性显示已更改。

不幸的是，当我执行WCF服务公开的方法之一时，它仍然使用TextMessageEncoding，我找不到原因。

我知道了，虽然工作，通过构建新的ClientBase和传递新的EndPointBinding在构造函数中：

socialProxy = new SocialProxyClient(SocialProxyClientSettings.SocialProxyMTomEndPointBinding, new EndpointAddress(SocialProxyClientSettings.SocialProxyEndPointAddress)); 

但是当我尝试这样它不工作：

socialProxy.Endpoint.Binding = SocialProxyClientSettings.SocialProxyMTomEndPointBinding; 

这些是我对EndPointBindings的定义：

public static TextMessageEncodingBindingElement TextMessageEncodingBindingElement 
{ 
    get 
    { 
     if (_textMessageEncodingBindingElement == null) 
     { 
      _textMessageEncodingBindingElement = new TextMessageEncodingBindingElement() { MessageVersion = MessageVersion.Soap11 }; 
      _textMessageEncodingBindingElement.ReaderQuotas = new System.Xml.XmlDictionaryReaderQuotas() 
      { 
       MaxDepth = 32, 
       MaxStringContentLength = 5242880, 
       MaxArrayLength = 204800000, 
       MaxBytesPerRead = 5242880, 
       MaxNameTableCharCount = 5242880 
      }; 
     } 
     return _textMessageEncodingBindingElement; 
    } 
} 

public static MtomMessageEncodingBindingElement MtomMessageEncodingBindingElement 
{ 
    get 
    { 
     if (_mtomMessageEncodingBindingElement == null) 
     { 
      _mtomMessageEncodingBindingElement = new MtomMessageEncodingBindingElement(); 
      _mtomMessageEncodingBindingElement.MaxReadPoolSize = TextMessageEncodingBindingElement.MaxReadPoolSize; 
      _mtomMessageEncodingBindingElement.MaxWritePoolSize = TextMessageEncodingBindingElement.MaxWritePoolSize; 
      _mtomMessageEncodingBindingElement.MessageVersion = TextMessageEncodingBindingElement.MessageVersion; 
      _mtomMessageEncodingBindingElement.ReaderQuotas.MaxDepth = TextMessageEncodingBindingElement.ReaderQuotas.MaxDepth; 
      _mtomMessageEncodingBindingElement.ReaderQuotas.MaxStringContentLength = TextMessageEncodingBindingElement.ReaderQuotas.MaxStringContentLength; 
      _mtomMessageEncodingBindingElement.ReaderQuotas.MaxArrayLength = TextMessageEncodingBindingElement.ReaderQuotas.MaxArrayLength; 
      _mtomMessageEncodingBindingElement.ReaderQuotas.MaxBytesPerRead = TextMessageEncodingBindingElement.ReaderQuotas.MaxBytesPerRead; 
      _mtomMessageEncodingBindingElement.ReaderQuotas.MaxNameTableCharCount = TextMessageEncodingBindingElement.ReaderQuotas.MaxNameTableCharCount; 
     } 
     return _mtomMessageEncodingBindingElement; 
    } 
} 

有人可以解释为什么chang Endpoint.Binding以编程方式不起作用？

Answer 1

我相信在构建ClientBase的时候，原始的Binding被用来创建一些帮助对象。稍后更改绑定不会更改这些帮助程序对象。

要在构建之后做出任何调整，您可能需要自定义绑定行为，您可以根据需要调整绑定的内部。在构造中使用它，以便为以后的更改准备好所有帮助程序对象。像往常一样，所有你想要的只是一个简单的行为改变，但你还需要编写辅助助手类来支持你的行为改变。

查看SO线程：ONVIF Authentication in .NET 4.0 with Visual Studio 2010 有关CustomBinding问题的讨论。

查看博客文章：Supporting the WS-I Basic Profile Password Digest in a WCF Client Proxy 有关自定义行为的示例，可让您即时更改用户名令牌。

也许可以做一些类似的事情，让您在运行中控制本地端点绑定。

更新：更多阅读在StackOverflow和它的页面链接，我相信我找到了你正在寻找的答案。

对于PasswordDigestBehavior： 看到：ONVIF Authentication in .NET 4.0 with Visual Studios 2010 和：http://benpowell.org/supporting-the-ws-i-basic-profile-password-digest-in-a-wcf-client-proxy/

对于本地网卡绑定： 见：Specify the outgoing IP address to use with WCF client

// ASSUMPTIONS: 
// 1: DeviceClient is generated by svcutil from your WSDL. 
// 1.1: DeviceClient is derived from 
//   System.ServiceModel.ClientBase<Your.Wsdl.Device> 
// 2: serviceAddress is the Uri provided for your service. 
// 
private static DeviceClient CreateDeviceClient(IPAddress nicAddress, 
               Uri serviceAddress, 
               String username, 
               String password) 
{ 
    if (null == serviceAddress) 
     throw new ArgumentNullException("serviceAddress"); 

    ////////////////////////////////////////////////////////////////////////////// 
    // I didn't know how to put a variable set of credentials into a static 
    // app.config file. 
    // But I found this article that talks about how to set up the right kind 
    // of binding on the fly. 
    // I also found the implementation of PasswordDigestBehavior to get it all to work. 
    // 
    // from: https://stackoverflow.com/questions/5638247/onvif-authentication-in-net-4-0-with-visual-studios-2010 
    // see: http://benpowell.org/supporting-the-ws-i-basic-profile-password-digest-in-a-wcf-client-proxy/ 
    // 
    EndpointAddress serviceEndpointAddress = new EndpointAddress(serviceAddress); 
    HttpTransportBindingElement httpBinding = new HttpTransportBindingElement(); 
    if (!String.IsNullOrEmpty(username)) 
    { 
     httpBinding.AuthenticationScheme = AuthenticationSchemes.Digest; 
    } 
    else 
    { 
     httpBinding.AuthenticationScheme = AuthenticationSchemes.Anonymous; 
    } 
    var messageElement = new TextMessageEncodingBindingElement(); 
    messageElement.MessageVersion = 
     MessageVersion.CreateVersion(EnvelopeVersion.Soap12, AddressingVersion.None); 

    CustomBinding bind = new CustomBinding(messageElement, httpBinding); 

    //////////////////////////////////////////////////////////////////////////////// 
    // from: https://stackoverflow.com/questions/3249846/specify-the-outgoing-ip-address-to-use-with-wcf-client 
    // Adjust the serviceEndpointAddress to bind to the local NIC, if at all possible. 
    // 
    ServicePoint sPoint = ServicePointManager.FindServicePoint(serviceAddress); 
    sPoint.BindIPEndPointDelegate = delegate(
      System.Net.ServicePoint servicePoint, 
      System.Net.IPEndPoint remoteEndPoint, 
      int retryCount) 
    { 
     // if we know our NIC local address, use it 
     // 
     if ((null != nicAddress) 
      && (nicAddress.AddressFamily == remoteEndPoint.AddressFamily)) 
     { 
      return new System.Net.IPEndPoint(nicAddress, 0); 
     } 
     else if (System.Net.Sockets.AddressFamily.InterNetworkV6 == remoteEndPoint.AddressFamily) 
     { 
      return new System.Net.IPEndPoint(System.Net.IPAddress.IPv6Any, 0); 
     } 
     else // if (System.Net.Sockets.AddressFamily.InterNetwork == remoteEndPoint.AddressFamily) 
     { 
      return new System.Net.IPEndPoint(System.Net.IPAddress.Any, 0); 
     } 
    }; 
    ///////////////////////////////////////////////////////////////////////////// 

    DeviceClient client = new DeviceClient(bind, serviceEndpointAddress); 

    // Add our custom behavior 
    // - this requires the Microsoft WSE 3.0 SDK file: Microsoft.Web.Services3.dll 
    // 
    PasswordDigestBehavior behavior = new PasswordDigestBehavior(username, password); 
    client.Endpoint.Behaviors.Add(behavior); 

    return client; 
}