WCF自定义绑定-无法计算Scheme，因为此CustomBinding缺少TransportBindingElement

Question

I am using custom binding and getting following error :

The Scheme cannot be computed for this binding because this CustomBinding lacks a TransportBindingElement. Every binding must have at least one binding element that derives from TransportBindingElement.

My Custom Binding Code as follows

public class MyCustomBinding : Binding
    {
        private HttpTransportBindingElement transport;
        private BinaryMessageEncodingBindingElement encoding;

        public MyCustomBinding()
            : base()
        {
            this.InitializeValue();
        }
        public override BindingElementCollection CreateBindingElements()
        {
            BindingElementCollection elements = new BindingElementCollection();
            elements.Add(this.encoding);
            elements.Add(this.transport);
            return elements;
        }
        public override string Scheme
        {
            get { return this.transport.Scheme; }
        }
        private void InitializeValue()
        {
            this.transport = new HttpTransportBindingElement();
            this.encoding = new BinaryMessageEncodingBindingElement();
        }
    }

    public class MyCustomBindingCollectionElement : BindingCollectionElement
    {
        // type of custom binding class
        public override Type BindingType
        {
            get { return typeof(MyCustomBinding); }
        }

       //  override ConfiguredBindings
        public override ReadOnlyCollection<IBindingConfigurationElement> ConfiguredBindings
        {
            get
            {
                return new ReadOnlyCollection<IBindingConfigurationElement>(
                new List<IBindingConfigurationElement>());
            }
        }

        // return Binding class object
        protected override Binding GetDefault()
        {
            return new MyCustomBinding();
        }

        public override bool ContainsKey(string name) {

            return true;
        }

        protected override bool TryAdd(string name, Binding binding, Configuration config)
        {
            return true;
        }
    }

Web.config code is as follows:

<extensions>
      <bindingExtensions>
        <!--<add name="ProxyElement" type="ADHA.Model.HttpTransportBindingElementProxy, ADHA"/>-->
      <add name="MyCustomBinding" type="ADHA.Model.MyCustomBindingCollectionElement,ADHA,
               Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
      </bindingExtensions>
    </extensions>

<service>      
    <services>
 <endpoint address="" binding="customBinding" bindingConfiguration="MyCustomBinding" contract="ADHA.IADHAService">
            </endpoint>
         <endpoint address="mex" binding="customBinding" contract="IMetadataExchange" />

      </service>      
    </services>

<bindings>
   <customBinding>
        <binding name="MyCustomBinding">
          <binaryMessageEncoding maxReadPoolSize="64" maxWritePoolSize="16"
                                 maxSessionSize="2048">
            <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
                     maxBytesPerRead="4096" maxNameTableCharCount="16384"/>
          </binaryMessageEncoding>        
          <textMessageEncoding
            messageVersion="Soap11WSAddressingAugust2004"/>
         <httpsTransport manualAddressing="false" maxBufferPoolSize="524288"
                         maxReceivedMessageSize="65536" allowCookies="false" authenticationScheme="Anonymous"
         bypassProxyOnLocal="false" decompressionEnabled="true" hostNameComparisonMode="StrongWildcard"
        keepAliveEnabled="true" maxBufferSize="65536" proxyAuthenticationScheme="Anonymous"
        realm="" transferMode="Buffered" unsafeConnectionNtlmAuthentication="false" useDefaultWebProxy="true"/>
        </binding>

      </customBinding>

    </bindings>

Someone please tell me whats wrong with my code?

Answer 1

See an example here ( http://webservices20.blogspot.de/2008/11/introducing-wcf-clearusernamebinding.html ). There is also a project on github with good working sample. You should refer your new type with the new name, defined in extension description. Like that:

<extensions>
  <bindingExtensions>
   <add name="myCustomBinding" type="ADHA.Model.MyCustomBindingCollectionElement, ADHA,
           Version=1.0.0.0, Culture=neutral, PublicKeyToken=null"/>
  </bindingExtensions>
</extensions>

<bindings>
  <myCustomBinding>
   <binding name="myCustomBindingConfig"> 
     <binaryMessageEncoding />
     <httpsTransport />
   </binding>
  </myCustomBinding>
</bindings>
<services>
  <service>
      <endpoint address="" binding="customBinding"
       bindingConfiguration="myCustomBindingConfig"
       contract="ADHA.IADHAService">
        </endpoint>
     <endpoint address="mex" binding="customBinding" contract="IMetadataExchange" />
  </service>      
</services>

For that you will have to create a Custom BindingElement with the Configuration.StandardBindingElement and a custom BindingCollectionElement with the Configuration.StandardBindingCollectionElement.

One more step by step example is here.