WCF常见问题(3) -- WCF 4.0 Simple Configuration 如何修改默认Binding

WCF 4.0 引入了一些新的特性，其中 Simple Configuration 大大简化了 WCF 的配置：结合 Service Markup 和默认Binding，WCF 开发者们只要更专心于逻辑的实现。先来看看 VS2010 下创建一个 WCF Service Application 后生成的配置文件：



【.NET 4.0 生成的配置文件】
[b]（只贴出来 ServiceModel 配置节的内容）[/b]
<system.serviceModel>
<behaviors>
<serviceBehaviors>
<behavior>
<!-- To avoid disclosing metadata information, set the value below to false and remove the metadata endpoint above before deployment -->
<serviceMetadata httpGetEnabled="true"/>
<!-- To receive exception details in faults for debugging purposes, set the value below to true. Set to false before deployment to avoid disclosing exception information -->
<serviceDebug includeExceptionDetailInFaults="false"/>
</behavior>
</serviceBehaviors>
</behaviors>
<serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
</system.serviceModel>
【.NET 3.5 生成的配置文件】
（只贴出来 ServiceModel 配置节的内容）
<system.serviceModel>
<services>
<service name="WcfService35.Service1" behaviorConfiguration="WcfService35.Service1Behavior">
<!-- Service Endpoints -->
<endpoint address="" binding="wsHttpBinding" contract="WcfService35.IService1">
<!--
Upon deployment, the following identity element should be removed or replaced to reflect the
identity under which the deployed service runs. If removed, WCF will infer an appropriate identity
automatically.
-->
<identity>
<dns value="localhost"/>
</identity>
</endpoint>
<endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior name="WcfService35.Service1Behavior">
<!-- To avoid disclosing metadata information, set the value below to false and remove the metadata endpoint above before deployment -->
<serviceMetadata httpGetEnabled="true"/>
<!-- To receive exception details in faults for debugging purposes, set the value below to true. Set to false before deployment to avoid disclosing exception information -->
<serviceDebug includeExceptionDetailInFaults="false"/>
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>通过比较可以发现 WCF 4.0 里去掉了 services 配置节，默认使用的是 BasicHttpBinding，整个配置简洁了很多。
但问题就来了，当需要使用 BasicHttpBinding 以外的 Binding 时该如何配置呢？下面提供几种方案来解决这个问题。

【方案1】 通过 WCF Config tool 添加 services 配置节，即还像 .net 3.5 一样把完整的 service 配置出来
:




然后在 Services 里添加 Service Endpoint ，注意：在 WCF Service Application 时，Address 不需要指定。



这样配置文件就修改OK了：
<system.serviceModel>
<services>
<service name="WcfSimpleConfigServiceApplication.Service1">
<endpoint address="" binding="wsHttpBinding" bindingConfiguration=""
contract="WcfSimpleConfigServiceApplication.IService1" />
</service>
</services>
<behaviors>
<serviceBehaviors>
<behavior>
<!-- To avoid disclosing metadata information, set the value below to false and remove the metadata endpoint above before deployment -->
<serviceMetadata httpGetEnabled="true"/>
<!-- To receive exception details in faults for debugging purposes, set the value below to true. Set to false before deployment to avoid disclosing exception information -->
<serviceDebug includeExceptionDetailInFaults="false"/>
</behavior>
</serviceBehaviors>
</behaviors>
<serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
</system.serviceModel>【方案2】利用 WCF 4.0里新增的 protocolMapping 配置节
这是最简单的解决方案，直接在 system.serviceModel 配置节中加入：
<protocolMapping> 
    <add binding="wsHttpBinding" scheme="http"/> 
</protocolMapping> 
通过协议-绑定的方式，WCF4.0框架自动选择 Binding。
【方案3】使用编程方式，添加Binding
首先来看看 Service1.svc 的 Markup：
<%@ ServiceHost Language="C#" Debug="true" Service="WcfSimpleConfigServiceApplication.Service1" CodeBehind="Service1.svc.cs" %>

在 WCF Services Application 这种工程模板里，是不需要你手动编码实现 Host 的，因为它使用的是 IIS Host，WCF框架通过上面的 Markup 默认使用 ServiceHostFactory  来加载 Service。当然 ServiceHostFactory 使用的是默认的 BasicHttpBinding。编程模式修改 Binding 就需要我们自己实现一个 HostFactory，添加不同的 Binding。（下面代码需要添加 System.ServiceModel.Activation.dll）
public class WsHttpBindingServiceHostFactory : ServiceHostFactory
{
protected override ServiceHost CreateServiceHost(Type serviceType, Uri[] baseAddresses)
{
ServiceHost host = new ServiceHost(serviceType, baseAddresses);
host.AddServiceEndpoint(typeof(IService1), new WSHttpBinding(), "");
return host;
}
}
然后在 Markup 里指明这个自定义的 HostFactory：
<%@ ServiceHost Language="C#" Debug="true" Factory="WcfSimpleConfigServiceApplication.WsHttpBindingServiceHostFactory" Service="WcfSimpleConfigServiceApplication.Service1" CodeBehind="Service1.svc.cs" %>

另外，不在 Markup 里指定，也可以通过 web.config 里配置实现，二者选其一：
<serviceHostingEnvironment multipleSiteBindingsEnabled="true">
<serviceActivations>
<add service="WcfSimpleConfigServiceApplication.Service1"
factory="WcfSimpleConfigServiceApplication.WsHttpBindingServiceHostFactory"
relativeAddress="Service1.svc"/>
</serviceActivations>
</serviceHostingEnvironment>
总的来说，第一种回归完全配置，不仅仅是Binding，自定义Binding行为时也需要要。第二种最简单快速。第三种方式，编程方式实现，
主要是在Factory上做文章。