Asp.net mvc 我的web.config中没有定义角色管理器部分

我在VS2010 express上创建了一个新的mvc4项目。现在我想向数据库添加角色。我正在使用PackageManager控制台运行updatedatabase命令来插入角色，它给了我以下错误

PM> Update-Database -verbose
Using StartUp project 'eManager.Web'.
Using NuGet project 'eManager.Web'.
Specify the '-Verbose' flag to view the SQL statements being applied to the target database.
Target database is: 'eManager.Web' (DataSource: .\SQLEXPRESS, Provider: System.Data.SqlClient, Origin: Configuration).
No pending code-based migrations.
Running Seed method.
System.Configuration.Provider.ProviderException: The Role Manager feature has not been enabled.
   at System.Web.Security.Roles.EnsureEnabled()
   at System.Web.Security.Roles.RoleExists(String roleName)
   at eManager.Web.Migrations.Configuration.Seed(DepartmentDb context) in C:\Users\Administrator\Desktop\eManager\eManager.Web\Migrations\Configuration.cs:line 26
   at System.Data.Entity.Migrations.DbMigrationsConfiguration`1.OnSeed(DbContext context)
   at System.Data.Entity.Migrations.DbMigrator.SeedDatabase()
   at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.SeedDatabase()
   at System.Data.Entity.Migrations.DbMigrator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   at System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update(String targetMigration)
   at System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.RunCore()
   at System.Data.Entity.Migrations.Design.ToolingFacade.BaseRunner.Run()

角色管理器功能尚未启用。

我需要启用角色管理器，但在web.config中找不到该部分

下面是web.config文件

  <?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=4.4.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <connectionStrings>
    <add name="DefaultConnection" connectionString="Data Source=.\SQLEXPRESS;Initial Catalog=eManager.Web;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\eManager.mdf " providerName="System.Data.SqlClient" />
  </connectionStrings>
  <appSettings>

          <!--<add key="enableSimpleMembership" value="true" />-->

    <add key="webpages:Version" value="2.0.0.0" />
    <add key="webpages:Enabled" value="false" />
    <add key="PreserveLoginUrl" value="true" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />
  </appSettings>
  <system.web>
    <compilation debug="true" targetFramework="4.0" />
    <authentication mode="Forms">
      <forms loginUrl="~/Account/Login" timeout="2880" />
    </authentication>
    <pages>
      <namespaces>
        <add namespace="System.Web.Helpers" />
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Optimization" />
        <add namespace="System.Web.Routing" />
        <add namespace="System.Web.WebPages" />
      </namespaces>
    </pages>
      <compilation debug="true" targetFramework="4.5">
          <assemblies>
              <add assembly="WebMatrix.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
              <add assembly="WebMatrix.WebData, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
          </assemblies>
      </compilation>
  </system.web>
  <system.webServer>
    <validation validateIntegratedModeConfiguration="false" />
    <modules runAllManagedModulesForAllRequests="true" />
    <handlers>
      <remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" />
      <remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" />
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
      <add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>
  </system.webServer>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
  </entityFramework>
</configuration>

---

默认情况下，该部分不存在，但您可以添加它

将其放入

e、 g

....

<system.web>
   <roleManager defaultProvider="CustomRoleProvider" >
     <providers>
       <clear />
       <add name="CustomRoleProvider" type="MyNamespace.CustomRoleProvider" />
     </providers>
   </roleManager>
   <compilation debug="true" targetFramework="4.0" />
....