我似乎无法解决实体框架6中常见的问题。我已经在SO上查看了与此问题相关的许多主题,但无法找到适用于我的特定情况的解决方案。
到目前为止,我一直在使用带有代码优先迁移的localdb进行开发,这很好。但是现在我将它移动到实际的SQL服务器实例,它会在尝试迁移时抛出以下错误:
" ADO.NET提供程序具有不变名称' System.Data.SqlClient;'要么未在计算机或应用程序配置文件中注册,要么无法加载。有关详细信息,请参阅内部异常 在System.Data.Common.DbProviderFactories.GetFactory(String providerInvariantName)"
我尝试了以下修复:
1)卸载并重新安装实体框架
2)添加code并使用:
public abstract class BaseDomainContext : DbContext
{
static BaseDomainContext()
{
// ROLA - This is a hack to ensure that Entity Framework SQL Provider is copied across to the output folder.
// As it is installed in the GAC, Copy Local does not work. It is required for probing.
// Fixed "Provider not loaded" error
var ensureDLLIsCopied = System.Data.Entity.SqlServer.SqlProviderServices.Instance;
}
}
作为我的DbSet类的基类。
3)将所有内容添加到新解决方案中并收到相同的错误。
4)删除了writecontext并尝试了只读的迁移,但仍然失败。
5)使用来自MSDN
的信息尝试了几次重写6)我已确认EntityFramework.SqlServer.dll位于我的bin目录中。它也被正确引用。另外,我的解决方案只有一个项目。
7)确认我没有在视图下使用WebConfig。
8)确认我在bin文件夹中有System.Data dll。
清理/重建并删除在上述每个步骤之后完成的现有迁移文件夹。
我无法解释为什么我仍然收到此错误。
Web配置
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 --></configSections>
<appSettings>
<add key="webpages:Version" value="3.0.0.0" />
<add key="webpages:Enabled" value="false" />
<add key="ClientValidationEnabled" value="true" />
<add key="UnobtrusiveJavaScriptEnabled" value="true" />
</appSettings>
<connectionStrings>
<add name="ReadContext" connectionString="Server=Sql2014intsnace;Database=database;User Id=secret; Password=secret;" providerName="System.Data.SqlClient;" />
<add name="WriteContext" connectionString="Server=Sql2014intsnace;Database=database;User Id=secret; Password=secret;" providerName="System.Data.SqlClient;" />
</connectionStrings>
<system.web>
<compilation debug="true" targetFramework="4.5" />
<httpRuntime targetFramework="4.5" />
<authentication mode="Windows" />
<authorization>
<deny users="?" />
</authorization>
</system.web>
<system.webServer>
<handlers>
<remove name="ExtensionlessUrlHandler-Integrated-4.0" />
<remove name="OPTIONSVerbHandler" />
<remove name="TRACEVerbHandler" />
<add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
</handlers>
</system.webServer>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin.Security.OAuth" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin.Security.Cookies" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin.Security" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Newtonsoft.Json" culture="neutral" publicKeyToken="30ad4fe6b2a6aeed" />
<bindingRedirect oldVersion="0.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-5.2.2.0" newVersion="5.2.2.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Optimization" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="1.1.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-1.5.2.14234" newVersion="1.5.2.14234" />
</dependentAssembly>
</assemblyBinding>
</runtime>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
</providers>
<contexts>
<context type="ProjectName.Models.ReadContext, ProjectName">
<databaseInitializer type="System.Data.Entity.MigrateDatabaseToLatestVersion`2[[ProjectName.Models.ReadContext, ProjectName], [ProjectName.Migrations.Configuration, ProjectName]], EntityFramework" />
</context>
</contexts>
</entityFramework>
</configuration>
答案 0 :(得分:12)
你有这个:
<add name="ReadContext"
connectionString="Server=Sql2014intsnace;Database=database;User Id=secret; Password=secret;"
providerName="System.Data.SqlClient;" /> <-- semi-colon
应该是这样的:
<add name="ReadContext"
connectionString="Server=Sql2014intsnace;Database=database;User Id=secret; Password=secret;"
providerName="System.Data.SqlClient" /> <-- no semi-colon
否则,您要告知ADO找到名为System.Data.SqlClient;
的提供商 - 没有提供商。
答案 1 :(得分:1)
我收到了这个错误,但对我来说这是完全不同的。我只能通过查看C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\machine.config
并找到答案来解决这个问题:
https://stackoverflow.com/a/9929534/3850405
然后我必须编辑:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\Config\machine.config
和
DbProviderFactories
搜索<system.data>
<DbProviderFactories>
<add name="IBM DB2 for i .NET Provider" invariant="IBM.Data.DB2.iSeries" description=".NET Framework Data Provider for IBM i" type="IBM.Data.DB2.iSeries.iDB2Factory, IBM.Data.DB2.iSeries, Version=12.0.0.0, Culture=neutral, PublicKeyToken=9cdb2ebfb1f93a26" />
</DbProviderFactories>
<DbProviderFactories />
</system.data>
这两个配置看起来像这样:
<DbProviderFactories />
当我删除尾随{
"relationship.name": "someting"
}
后,所有内容都重新开始工作。
答案 2 :(得分:-2)
对我来说,这个问题是由EntityFramework损坏引起的。卸载EntityFramework以及Visual Studio并重新安装Visual Studio - Visual Studio安装涵盖了解决此问题的.Net Framework SDK安装类型。