为什么我的WCF数据服务第二次运行时无法启动？

Question

我使用Visual Studio 2015创建了一个包含WCF数据服务的ASP.NET应用程序，其基于the AdventureWorks2014 OLTP，并遵循this walkthrough。

当我构建应用程序并在调试器（在IIS Express上）中运行它时，该服务加载正常，我看到XML元数据显示在浏览器中，并且可以进一步请求子路径以查看我的数据库的行。只要调试会话继续，我可以继续发出这样的请求。

一旦我停止调试器并重新启动它，没有之间的重建，我的浏览器，而不是显示一个错误：

The type 'AdventureWorks.Internal.WebService.DataService', provided as the Service attribute value in the ServiceHost directive, or provided in the configuration element system.serviceModel/serviceHostingEnvironment/serviceActivations could not be found.

[InvalidOperationException: The type 'AdventureWorks.Internal.WebService.DataService', provided as the Service attribute value in the ServiceHost directive, or provided in the configuration element system.serviceModel/serviceHostingEnvironment/serviceActivations could not be found.] 
    System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) +741 
    System.ServiceModel.HostingManager.CreateService(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) +1417 
    System.ServiceModel.HostingManager.ActivateService(ServiceActivationInfo serviceActivationInfo, EventTraceActivity eventTraceActivity) +53 
    System.ServiceModel.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath, EventTraceActivity eventTraceActivity) +660 

[ServiceActivationException: The service '/DataService.svc' cannot be activated due to an exception during compilation. The exception message is: The type 'AdventureWorks.Internal.WebService.DataService', provided as the Service attribute value in the ServiceHost directive, or provided in the configuration element system.serviceModel/serviceHostingEnvironment/serviceActivations could not be found..] 
    System.Runtime.AsyncResult.End(IAsyncResult result) +386 
    System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result) +174 
    System.ServiceModel.Activation.ServiceHttpHandler.EndProcessRequest(IAsyncResult result) +7 
    System.Web.CallHandlerExecutionStep.OnAsyncHandlerCompletion(IAsyncResult ar) +129 

这发生在我开发无论是在Visual Studio 2015年或 我使用的Windows 10与我的ASP.NET应用程序的目标是.NET Framework 4.6.1。

DataService.svc：

<%@ ServiceHost Language="C#" Factory="System.ServiceModel.Activation.WebServiceHostFactory, System.ServiceModel.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" Service="AdventureWorks.Internal.WebService.DataService" %> 

DataService.svc.cs：

namespace AdventureWorks.Internal.WebService 
{ 
    //[ServiceBehavior(IncludeExceptionDetailInFaults = true)] 
    public class DataService : DataService<AdventureWorksDatabaseEntities> 
    { 
     // This method is called only once to initialize service-wide policies. 
     public static void InitializeService(DataServiceConfiguration config) 
     { 
      config.SetEntitySetAccessRule("*", EntitySetRights.All); 
      config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V3; 
     } 
    } 
} 

Web.config：

<?xml version="1.0" encoding="utf-8"?> 
<!-- 
    For more information on how to configure your ASP.NET application, please visit 
    http://go.microsoft.com/fwlink/?LinkId=169433 
    --> 
<configuration> 
    <configSections> 
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 --> 
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" /> 
    </configSections> 
    <system.web> 
    <compilation debug="true" targetFramework="4.6.1" /> 
    <httpRuntime targetFramework="4.6.1" /> 
    <httpModules> 
     <add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web" /> 
    </httpModules> 
    </system.web> 
    <system.codedom> 
    <compilers> 
     <compiler language="c#;cs;csharp" extension=".cs" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:6 /nowarn:1659;1699;1701" /> 
     <compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:14 /nowarn:41008 /define:_MYTYPE=\&quot;Web\&quot; /optionInfer+" /> 
    </compilers> 
    </system.codedom> 
    <system.webServer> 
    <validation validateIntegratedModeConfiguration="false" /> 
    <modules> 
     <remove name="ApplicationInsightsWebTracking" /> 
     <add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web" preCondition="managedHandler" /> 
    </modules> 
    </system.webServer> 
    <connectionStrings> 
    <add name="AdventureWorksDatabaseEntities" connectionString="metadata=res://*/DataModel.csdl|res://*/DataModel.ssdl|res://*/DataModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=(LocalDB)\MSSQLLocalDB;attachdbfilename=|DataDirectory|\AdventureWorksDatabase.mdf;integrated security=True;connect timeout=30;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" /> 
    </connectionStrings> 
    <entityFramework> 
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework"> 
     <parameters> 
     <parameter value="v13.0" /> 
     </parameters> 
    </defaultConnectionFactory> 
    </entityFramework> 
    <system.serviceModel> 
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" /> 
    </system.serviceModel> 
</configuration> 

Answer 1

的发生是由于命名不一致此错误。请检查所有的命名空间。它应该工作。