ServiceHost 仅支持类服务类型。 wcf答案

【问题标题】：ServiceHost only supports class service types. wcfServiceHost 仅支持类服务类型。 wcf
【发布时间】：2020-10-25 09:09:50
【问题描述】：

我刚刚创建了一个 Web 应用程序。我使用 wcf 服务文件。我怎么无法从这个本地 Web 服务获取服务参考。

这是我的屏幕截图：

这是我的本地 wcf 服务文件：

<%@ ServiceHost Language="C#" Debug="true" Service="Admin_Staff_Care.SC_WCF.IRestServiceImpl" CodeBehind="~/App_Code/RestServiceImplClient.cs" %>

但我无法获得这些方法。使用 Project > Add Web reference > 然后我按照以下步骤操作：

然后我扩展服务然后我显示这条消息：

There was an error downloading 'http://localhost:4870/RestServiceImplClient.svc/$metadata'.
The request failed with the error message:
--
<!DOCTYPE html>
<html>
    <head>
        <title>ServiceHost only supports class service types.</title>
        <meta name="viewport" content="width=device-width" />
        <style>
         body {font-family:"Verdana";font-weight:normal;font-size: .7em;color:black;} 
         p {font-family:"Verdana";font-weight:normal;color:black;margin-top: -5px}
         b {font-family:"Verdana";font-weight:bold;color:black;margin-top: -5px}
         H1 { font-family:"Verdana";font-weight:normal;font-size:18pt;color:red }
         H2 { font-family:"Verdana";font-weight:normal;font-size:14pt;color:maroon }
         pre {font-family:"Consolas","Lucida Console",Monospace;font-size:11pt;margin:0;padding:0.5em;line-height:14pt}
         .marker {font-weight: bold; color: black;text-decoration: none;}
         .version {color: gray;}
         .error {margin-bottom: 10px;}
         .expandable { text-decoration:underline; font-weight:bold; color:navy; cursor:pointer; }
         @media screen and (max-width: 639px) {
          pre { width: 440px; overflow: auto; white-space: pre-wrap; word-wrap: break-word; }
         }
         @media screen and (max-width: 479px) {
          pre { width: 280px; }
         }
        </style>
    </head>

    <body bgcolor="white">

            <span><H1>Server Error in '/' Application.<hr width=100% size=1 color=silver></H1>

            <h2> <i>ServiceHost only supports class service types.</i> </h2></span>

            <font face="Arial, Helvetica, Geneva, SunSans-Regular, sans-serif ">

            <b> Description: </b>An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

            <br><br>

            <b> Exception Details: </b>System.ArgumentException: ServiceHost only supports class service types.<br><br>

            <b>Source Error:</b> <br><br>

            <table width=100% bgcolor="#ffffcc">
               <tr>
                  <td>
                      <code>

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.                      </code>

                  </td>
               </tr>
            </table>

            <br>

            <b>Stack Trace:</b> <br><br>

            <table width=100% bgcolor="#ffffcc">
               <tr>
                  <td>
                      <code><pre>

[ArgumentException: ServiceHost only supports class service types.]
   System.ServiceModel.Description.ServiceDescription.GetService(Type serviceType) +13498366
   System.ServiceModel.ServiceHost.CreateDescription(IDictionary`2& implementedContracts) +60
   System.ServiceModel.ServiceHostBase.InitializeDescription(UriSchemeKeyedCollection baseAddresses) +148
   System.ServiceModel.ServiceHost.InitializeDescription(Type serviceType, UriSchemeKeyedCollection baseAddresses) +49
   System.ServiceModel.ServiceHost..ctor(Type serviceType, Uri[] baseAddresses) +153
   System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(Type serviceType, Uri[] baseAddresses) +34
   System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) +538
   System.ServiceModel.HostingManager.CreateService(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) +1489
   System.ServiceModel.HostingManager.ActivateService(ServiceActivationInfo serviceActivationInfo, EventTraceActivity eventTraceActivity) +53
   System.ServiceModel.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) +666

[ServiceActivationException: The service '/RestServiceImplClient.svc' cannot be activated due to an exception during compilation.  The exception message is: ServiceHost only supports class service types..]
   System.Runtime.AsyncResult.End(IAsyncResult result) +513025
   System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result) +182
   System.ServiceModel.Activation.ServiceHttpModule.EndProcessRequest(IAsyncResult ar) +365683
   System.Web.AsyncEventExecutionStep.InvokeEndHandler(IAsyncResult ar) +165
   System.Web.AsyncEventExecutionStep.OnAsyncEventCompletion(IAsyncResult ar) +9930149
</pre>                      </code>

                  </td>
               </tr>
            </table>

            <br>

            <hr width=100% size=1 color=silver>

            <b>Version Information:</b> Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.8.4250.0

            </font>

    </body>
</html>
<!-- 
[ArgumentException]: ServiceHost only supports class service types.
   at System.ServiceModel.Description.ServiceDescription.GetService(Type serviceType)
   at System.ServiceModel.ServiceHost.CreateDescription(IDictionary`2& implementedContracts)
   at System.ServiceModel.ServiceHostBase.InitializeDescription(UriSchemeKeyedCollection baseAddresses)
   at System.ServiceModel.ServiceHost.InitializeDescription(Type serviceType, UriSchemeKeyedCollection baseAddresses)
   at System.ServiceModel.ServiceHost..ctor(Type serviceType, Uri[] baseAddresses)
   at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(Type serviceType, Uri[] baseAddresses)
   at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CreateService(String normalizedVirtualPath, EventTraceActivity eventTraceActivity)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(ServiceActivationInfo serviceActivationInfo, EventTraceActivity eventTraceActivity)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity)
[ServiceActivationException]: The service '/RestServiceImplClient.svc' cannot be activated due to an exception during compilation.  The exception message is: ServiceHost only supports class service types..
   at System.Runtime.AsyncResult.End[TAsyncResult](IAsyncResult result)
   at System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result)
   at System.ServiceModel.Activation.ServiceHttpModule.EndProcessRequest(IAsyncResult ar)
   at System.Web.HttpApplication.AsyncEventExecutionStep.InvokeEndHandler(IAsyncResult ar)
   at System.Web.HttpApplication.AsyncEventExecutionStep.OnAsyncEventCompletion(IAsyncResult ar)
-->
--.
Metadata contains a reference that cannot be resolved: 'http://localhost:4870/RestServiceImplClient.svc'.
The requested service, 'http://localhost:4870/RestServiceImplClient.svc' could not be activated. See the server's diagnostic trace logs for more information.
If the service is defined in the current solution, try building the solution and adding the service reference again.

我如何解决这个问题请帮助我....

WCF 项目 app.config 的第二次更新

<?xml version="1.0"?>
<configuration>

  <appSettings>
    <add key="aspnet:UseTaskFriendlySynchronizationContext" value="true" />
  </appSettings>
  <system.web>
    <compilation debug="true" targetFramework="4.7.2" />
    <httpRuntime targetFramework="4.7.2"/>
  </system.web>

  <system.serviceModel>
    <services>
      <service name="WcfService5.Service1"
               behaviorConfiguration="CalculatorServiceBehavior">
        <endpoint address=""
                  binding="basicHttpBinding"
                  contract="WcfService5.IService1"
                  bindingConfiguration="LargeWeb"/>
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="CalculatorServiceBehavior">
          <serviceMetadata httpGetEnabled="true" httpsGetEnabled="true" />
          <serviceDebug includeExceptionDetailInFaults="true" />
        </behavior>
      </serviceBehaviors>
    </behaviors>


    <bindings>
      <basicHttpBinding>
        <binding name="LargeWeb" maxBufferSize="2147483647" maxReceivedMessageSize="2147483647">
          <readerQuotas maxDepth="32" maxStringContentLength="2147483647" maxArrayLength="2147483647" maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" />
        </binding>
      </basicHttpBinding>
    </bindings>


  </system.serviceModel>

  <system.webServer>
    <modules runAllManagedModulesForAllRequests="true"/>
    <!--
        To browse web app root directory during debugging, set the value below to true.
        Set to false before deployment to avoid disclosing web app folder information.
      -->
    <directoryBrowse enabled="true"/>
  </system.webServer>

</configuration>

Web 应用程序 Web.config 的第二次更新

<system.serviceModel>
    <bindings>
      <basicHttpBinding>
        <binding name="BasicHttpBinding_IService1"/>
      </basicHttpBinding>
    </bindings>
    <client>
      <endpoint address="http://desktop-684ueha:8000/Service1.svc" binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_IService1" contract="IService1" name="BasicHttpBinding_IService1"/>
    </client>
  </system.serviceModel>

【问题讨论】：

标签： asp.net wcf c#-4.0

【解决方案1】：

这个错误是因为你在本地wcf服务文件中输入了错误的debug属性值，这里debug的属性值应该是实现的服务类类型，而不是服务接口。

将图中的IRestServiceImpl改为实现该接口的服务类。

可以先将wcf服务发布到iis，测试是否可以正常调用服务。然后向客户端添加服务引用。

【讨论】：

我听从了你的建议，但仍然出现这样的错误：There was an error downloading 'http://localhost:4870/bin/RestServiceImplClient.svc/$metadata'. The request failed with HTTP status 404: Not Found. Metadata contains a reference that cannot be resolved: 'http://localhost:4870/bin/RestServiceImplClient.svc'. There was no endpoint listening at http://localhost:4870/bin/RestServiceImplClient.svc that could accept the message. This is often caused by an incorrect address or SOAP action. See InnerException,
我只是使用 localhost web 服务，但仍然出现错误，例如：The server was unable to process the request due to an internal error. For more information about the error, either turn on IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the <serviceDebug> configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework SDK documentation and inspect the server trace logs.
你能提供一些关于服务配置和SVC文件的信息吗？
你的APP.config文件是什么样的？
你的服务应该是WcfService5.IService1，但是你的svc文件里的服务是Admin_Staff_Care.SC_WCF.IRestServiceImpl，我觉得可能是这个问题。