wcf中的mextcpbinding-IMetadataExchange错误

我想让一个通过TCP的WCF服务工作。我在修改自己的项目时遇到了一些问题,所以我想从VS2008中包含的“基础”WCF模板开始。

以下是初始wcf app.config,当我运行该服务时,wcf测试客户端可以正常使用它:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <system.web>
        <compilation debug="true" />
    </system.web>
    <system.serviceModel>
        <services>
            <service name="WcfTcpTest.Service1" behaviorConfiguration="WcfTcpTest.Service1Behavior">
                <host>
                    <baseAddresses>
                        <add baseAddress="http://localhost:8731/Design_Time_Addresses/WcfTcpTest/Service1/" />
                    </baseAddresses>
                </host>
                <endpoint address="" binding="wsHttpBinding" contract="WcfTcpTest.IService1">
                    <identity>
                        <dns value="localhost"/>
                    </identity>
                </endpoint>
                <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
            </service>
        </services>
        <behaviors>
            <serviceBehaviors>
                <behavior name="WcfTcpTest.Service1Behavior">
                    <serviceMetadata httpGetEnabled="True"/>
                    <serviceDebug includeExceptionDetailInFaults="True" />
                </behavior>
            </serviceBehaviors>
        </behaviors>
    </system.serviceModel>
</configuration>

这完全有效,没有任何问题。

我认为将其从http更改为tcp很简单:更改绑定到其tcp等效项,并删除httpgetEnabled ServiceMetadata元素:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <system.web>
        <compilation debug="true" />
    </system.web>
    <system.serviceModel>
        <services>
            <service name="WcfTcpTest.Service1" behaviorConfiguration="WcfTcpTest.Service1Behavior">
                <host>
                    <baseAddresses>
                        <add baseAddress="net.tcp://localhost:1337/Service1/" />
                    </baseAddresses>
                </host>
                <endpoint address="" binding="netTcpBinding" contract="WcfTcpTest.IService1">
                    <identity>
                        <dns value="localhost"/>
                    </identity>
                </endpoint>
                <endpoint address="mex" binding="mexTcpBinding" contract="IMetadataExchange"/>
            </service>
        </services>
        <behaviors>
            <serviceBehaviors>
                <behavior name="WcfTcpTest.Service1Behavior">
                    <serviceDebug includeExceptionDetailInFaults="True" />
                </behavior>
            </serviceBehaviors>
        </behaviors>
    </system.serviceModel>
</configuration>

但当我运行此命令时,在WCF服务主机中会出现此错误:

System.InvalidOperationException:在服务服务1实施的合同列表中找不到合同名称“IMetadataExchange”。将ServiceMetadataBehavior直接添加到配置文件或ServiceHost,以启用对此合同的支持。

我觉得您不能使用TCP发送元数据,但事实就是这样,为什么有一个mextcpbinding选项?