ConfigurationManager.AppSettings 为空？

我有一个 VS2008 ASP.NET Web 服务应用程序在 XP 计算机的本地 IIS 上运行。同一解决方案中的单独项目使用测试方法来调用 WS 调用并运行其流程。

当我向 WS App 添加 Web 引用时，VS2008 在 Properties 文件夹中创建了一个 Settings.settings 文件来存储 Web 引用的地址。此过程还在 Web.config 文件中创建了一个名为 applicationSettings 的新部分，用于存储 Settings.settings 中的值

当我的应用程序尝试通过 ConfigurationManager.AppSettings[key] 从 Web.config 文件的 appSettings 部分检索配置值时，所有值均为 null，并且 AppSettings.AllKeys.Length 始终为零。

我什至将 Web.config 文件恢复到添加 Web 引用之前的状态，并确保它与系统生成的新项目的 web.config 文件完全相同，并且工作正常。在比较恢复的 Web.config 和新的 Web.config 后，我在 appSettings 部分添加了一个简单的值，但 ConfigurationManager.AppSettings[key] 仍然没有成功。

这是恢复后的 Web.config，无法从中读取

    <?xml version="1.0"?>

<configuration>
  <configSections>
    <sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
      <sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
        <section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptResourceHandlerSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
        <sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebServicesSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
          <section name="jsonSerialization" type="System.Web.Configuration.ScriptingJsonSerializationSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="Everywhere" />
          <section name="profileService" type="System.Web.Configuration.ScriptingProfileServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication" />
          <section name="authenticationService" type="System.Web.Configuration.ScriptingAuthenticationServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication" />
          <section name="roleService" type="System.Web.Configuration.ScriptingRoleServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication" />
        </sectionGroup>
      </sectionGroup>
    </sectionGroup>
  </configSections>

  <appSettings>
    <add key="testkey" value="testvalue"/>
  </appSettings>

  <connectionStrings/>

  <system.web>
      <!-- 
          Set compilation debug="true" to insert debugging 
          symbols into the compiled page. Because this 
          affects performance, set this value to true only 
          during development.
      -->
      <compilation debug="false">

        <assemblies>
          <add assembly="System.Core, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
          <add assembly="System.Data.DataSetExtensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
          <add assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
          <add assembly="System.Xml.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
        </assemblies>

      </compilation>
      <!--
          The <authentication> section enables configuration 
          of the security authentication mode used by 
          ASP.NET to identify an incoming user. 
      -->
      <authentication mode="Windows" />
      <!--
          The <customErrors> section enables configuration 
          of what to do if/when an unhandled error occurs 
          during the execution of a request. Specifically, 
          it enables developers to configure html error pages 
          to be displayed in place of a error stack trace.

      <customErrors mode="RemoteOnly" defaultRedirect="GenericErrorPage.htm">
          <error statusCode="403" redirect="NoAccess.htm" />
          <error statusCode="404" redirect="FileNotFound.htm" />
      </customErrors>
      -->

    <pages>
      <controls>
        <add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
        <add tagPrefix="asp" namespace="System.Web.UI.WebControls" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
      </controls>
    </pages>

    <httpHandlers>
      <remove verb="*" path="*.asmx"/>
      <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
      <add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
      <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" validate="false"/>
    </httpHandlers>
    <httpModules>
      <add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    </httpModules>


  </system.web>

  <system.codedom>
    <compilers>
      <compiler language="c#;cs;csharp" extension=".cs" warningLevel="4"
                type="Microsoft.CSharp.CSharpCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
        <providerOption name="CompilerVersion" value="v3.5"/>
        <providerOption name="WarnAsError" value="false"/>
      </compiler>
    </compilers>
  </system.codedom>

  <!-- 
      The system.webServer section is required for running ASP.NET AJAX under Internet
      Information Services 7.0.  It is not necessary for previous version of IIS.
  -->
  <system.webServer>
    <validation validateIntegratedModeConfiguration="false"/>
    <modules>
      <remove name="ScriptModule" />
      <add name="ScriptModule" preCondition="managedHandler" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
    </modules>
    <handlers>
      <remove name="WebServiceHandlerFactory-Integrated"/>
      <remove name="ScriptHandlerFactory" />
      <remove name="ScriptHandlerFactoryAppServices" />
      <remove name="ScriptResource" />
      <add name="ScriptHandlerFactory" verb="*" path="*.asmx" preCondition="integratedMode"
           type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
      <add name="ScriptHandlerFactoryAppServices" verb="*" path="*_AppService.axd" preCondition="integratedMode"
           type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
      <add name="ScriptResource" preCondition="integratedMode" verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
    </handlers>
  </system.webServer>

  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Extensions" publicKeyToken="31bf3856ad364e35"/>
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35"/>
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

有没有人经历过这个，或者知道如何解决这个问题？

TIA

-Matt

当您在 VS 项目中添加 *.Settings 文件时，其内容不会转到 app.config 文件。

VS 自动创建一个类（在你的例子中它被称为Settings）继承自应用程序设置库并在构建过程中自动嵌入到您的 dll/exe 中。

为了获取存储的设置，您只需在代码中创建 Settings 类的实例并从其公共属性中获取值。