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】

（只贴出来 ServiceModel 配置节的内容）

<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。