找不到实体框架ADO.NET Sql.Data.Client提供程序

Question

我有一个与问题“找不到具有固定名称”System.Data.SqlClient“的ADO.NET提供程序的实体框架提供程序”中提供的问题类似的问题，错误包含以下消息：

“具有固定名称”System.Data.SqlClient“的ADO.NET提供程序未在计算机或应用程序配置文件中注册，或者无法加载。有关详细信息，请参阅内部异常。”

正如相关问题的答案所提示的，我已经通过包管理器控制台重新安装了实体框架(EF6)，但错误仍然存在。我还检查了EntityFramework.sqlserver.dll是否在我的项目中被引用。下面是存储在app.config中的连接字符串：

<add name="DesignModel"    ConnectionString="metadata=res://*/DesignModel.csdl|res://*/DesignModel.ssdl|res://*/DesignModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=C071E;initial catalog=CTD2;integrated security=True;multipleactiveresultsets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />     

DesignModel designContext = new DesignModel();
designContext.MoPerfIDs.Load();

以下是完整的app.config：

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
       <section name="ppe.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
    </sectionGroup>
    <!-- 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=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>

  <connectionStrings>
    <add name="DesignModel" connectionString="metadata=res://*/DesignModel.csdl|res://*/DesignModel.ssdl|res://*/Design    Model.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=MONNMC071E;initial catalog=CTD2;integrated security=True;multipleactiveresultsets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />
  </connectionStrings>

<entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework">
        <parameters>
            <parameter value="System.Data.SqlClient" />
        </parameters>
    </defaultConnectionFactory>
    <providers>
        <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
</entityFramework>
</configuration>

任何帮助都将不胜感激。提前道谢。

Answer 1

您需要为System.Data.SqlClient SQL连接类型注册实体框架提供程序。在app.config中应该有：

<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=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
      <parameters>
        <parameter value="v11.0" />
      </parameters>
    </defaultConnectionFactory>
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>