MvcMiniProfiler无法转换EFProfiledDbConnection类型的对象

Question

我正在尝试将MvcMiniProfiler集成到我的asp.net mvc +实体framewok项目中.第一次Web请求时一切正常,但是在其他请求中给出了异常.

我的项目是
MVC 3
实体框架4.1(DatabaseFirst + POCO生成器DbContext)
MvcMiniProfiler.dll 1.9.0.0
MvcMiniProfiler.EntityFramework.dll 1.9.1.0
我从Nu-Get安装MvcMiniProfiler

下面添加到global.asax

    protected void Application_BeginRequest()
    {
        if (Request.IsLocal)
        {
            MvcMiniProfiler.MiniProfiler.Start();
            MiniProfilerEF.Initialize();       
        }
    }

下面添加到web.config

   <system.data>
    <DbProviderFactories>
      <remove invariant="MvcMiniProfiler.Data.ProfiledDbProvider" />
      <add name="MvcMiniProfiler.Data.ProfiledDbProvider" invariant="MvcMiniProfiler.Data.ProfiledDbProvider" description="MvcMiniProfiler.Data.ProfiledDbProvider" type="MvcMiniProfiler.Data.ProfiledDbProviderFactory, MvcMiniProfiler, Version=1.8.0.0, Culture=neutral, PublicKeyToken=b44f9351044011a3" />
    </DbProviderFactories>
  </system.data>

我得到了这个例外

    System.InvalidCastException was unhandled by user code
  Message=Unable to cast object of type 'MvcMiniProfiler.Data.EFProfiledDbConnection' to type 'System.Data.SqlClient.SqlConnection'.
  Source=System.Data
  StackTrace:
       at System.Data.SqlClient.SqlCommand.set_DbConnection(DbConnection value)
       at System.Data.Common.DbCommand.set_Connection(DbConnection value)
       at MvcMiniProfiler.Data.ProfiledDbCommand.set_DbConnection(DbConnection value) in C:\Users\sam\Desktop\mvc-mini-profiler\MvcMiniProfiler\Data\ProfiledDbCommand.cs:line 118
       at System.Data.Common.DbCommand.set_Connection(DbConnection value)
       at System.Data.Common.Utils.CommandHelper.SetStoreProviderCommandState(EntityCommand entityCommand, EntityTransaction entityTransaction, DbCommand storeProviderCommand)
       at System.Data.EntityClient.EntityCommandDefinition.ExecuteStoreCommands(EntityCommand entityCommand, CommandBehavior behavior)
       at System.Data.Objects.Internal.ObjectQueryExecutionPlan.Execute[TResultType](ObjectContext context, ObjectParameterCollection parameterValues)

EF调用中发生异常

ModaEntitiesWrapper.GetInstance().Articles
               .AsNoTracking()
               .Where(p => p.StatusId == 1).ToList();

如果我将Web.Config中的MvcMiniProfiler.Data.ProfiledDbProvider版本从1.8.0.0更改为1.9.0.0 MiniProfilerEF.Initialize()调用中出现了一种新的异常.

System.IndexOutOfRangeException was unhandled by user code
  Message=The given DataRow is not in the current DataRowCollection.
  Source=System.Data
  StackTrace:
       at System.Data.DataRowCollection.Remove(DataRow row)
       at MvcMiniProfiler.MiniProfilerEF.Initialize() 

Answer 1

也许这会有所帮助.移动MiniProfilerEF.Initialize();到方法的顶部Application_Start().请注意,在EF 4.1及更高版本中,应该调用所调用的方法MiniProfilerEF.Initialize_EF42();.

protected void Application_Start() {
    Logger.Info("Application start");
    MiniProfilerEF.Initialize_EF42();
    // ...
}

Answer 2

查看http://code.google.com/p/mvc-mini-profiler/

以下是如何将 mvc-mini-profiler 与 EF Database First 结合使用的示例：

public static class Entities
{
    public static MyEntities Create()
    {
         var builder = new EntityConnectionStringBuilder(ConfigurationManager.ConnectionStrings["MyEntities"].ConnectionString);
         var sqlConnection = new SqlConnection(builder.ProviderConnectionString);
         var profiledConnection = new EFProfiledDbConnection(sqlConnection, MiniProfiler.Current);

         return profiledConnection.CreateObjectContext<MyEntities>();
    }
}

然后，您可以使用该方法向 IOC 容器注册您的实体，或者使用类似的方法

using(var entities = Entities.Create())
{
    //Do stuff here
    entities.SaveChanges();
}

编辑：忘记添加

MiniProfilerEF.Initialize();

这仅用于 EF Code First。