实体框架4.1 - EFTracingProvider

Question

有没有办法使EFTracing provider与EF 4.1一起工作？

EFTracing似乎需要一个objectcontext，我使用dbcontext。

在此先感谢！

Answer 1

是的，你可以。我将community version与数据库优先DbContexts和代码优先DbContexts结合使用。此答案基于项目网站上的discussion thread。

对于数据库一/设计师DbContexts（通过ADO.NET DbContext Generator templates），你可以简单地添加下面的构造：

public abstract class MyDbContext : DbContext 
{ 
    protected MyDbContext(string nameOrConnectionString) 
     : base(EFTracingProviderUtils.CreateTracedEntityConnection(nameOrConnectionString), true) 
    { 
     // enable sql tracing 
     ((IObjectContextAdapter) this).ObjectContext.EnableTracing(); 
    } 
} 

对于代码，因为EFTracingProvider想要一个完整的实体连接字符串第一DbContexts它有点复杂。您必须手动创建EFTracingConnection实例。以下示例将适用于数据库优先和代码优先上下文。

public abstract class MyDbContext : DbContext 
{ 
    protected MyDbContext(string nameOrConnectionString) 
     : base(CreateTracingConnection(nameOrConnectionString), true) 
    { 
     // enable sql tracing 
     ((IObjectContextAdapter) this).ObjectContext.EnableTracing(); 
    } 

    private static DbConnection CreateTracingConnection(string nameOrConnectionString) 
    { 
     try 
     { 
      // this only supports entity connection strings http://msdn.microsoft.com/en-us/library/cc716756.aspx 
      return EFTracingProviderUtils.CreateTracedEntityConnection(nameOrConnectionString); 
     } 
     catch (ArgumentException) 
     { 
      // an invalid entity connection string is assumed to be a normal connection string name or connection string (Code First) 

      ConnectionStringSettings connectionStringSetting = 
       ConfigurationManager.ConnectionStrings[nameOrConnectionString]; 
      string connectionString; 
      string providerName; 

      if (connectionStringSetting != null) 
      { 
       connectionString = connectionStringSetting.ConnectionString; 
       providerName = connectionStringSetting.ProviderName; 
      } 
      else 
      { 
       providerName = "System.Data.SqlClient"; 
       connectionString = nameOrConnectionString; 
      } 

      return CreateTracingConnection(connectionString, providerName); 
     } 
    } 

    private static EFTracingConnection CreateTracingConnection(string connectionString, string providerInvariantName) 
    { 
     // based on the example at http://jkowalski.com/2010/04/23/logging-sql-statements-in-entity-frameworkcode-first/ 
     string wrapperConnectionString = 
      String.Format(@"wrappedProvider={0};{1}", providerInvariantName, connectionString); 

     EFTracingConnection connection = 
      new EFTracingConnection 
       { 
        ConnectionString = wrapperConnectionString 
       }; 

     return connection; 
    } 
} 

Answer 2

如果您正在使用的DbContext和MVC模型首先，使用EntityConnections然后将下面的示例代码应该是意味着你需要：

public partial class BrickHouseFitnessContext : DbContext 
{ 

    public BrickHouseFitnessContext(): base(EntityConnectionWrapperUtils.CreateEntityConnectionWithWrappers(ConfigurationManager.ConnectionStrings["BrickHouseFitnessContext"].ConnectionString, "EFTracingProvider"), true) 
    { 
    } 

另外：

在web.config文件添加以下部分：

<system.data> 
<DbProviderFactories> 
    <add name="EF Tracing Data Provider" invariant="EFTracingProvider" description="Tracing Provider Wrapper" type="EFTracingProvider.EFTracingProviderFactory, EFTracingProvider, Version=1.0.0.0, Culture=neutral, PublicKeyToken=def642f226e0e59b" /> 
    <add name="EF Generic Provider Wrapper" invariant="EFProviderWrapper" description="Generic Provider Wrapper" type="EFProviderWrapperToolkit.EFProviderWrapperFactory, EFProviderWrapperToolkit, Version=1.0.0.0, Culture=neutral, PublicKeyToken=def642f226e0e59b" /> 
</DbProviderFactories> 

和：

<add key="EFTracingProvider.logToConsole" value="true" /> 
<add key="EFTracingProvider.logToFile" value="C:\BrickHouseFitnessSqlLog.txt" /> 

有没有必要列入ExtendedEntities还是原来的文章中提到的其他的ObjectContext派生类。运行该代码，您应该看到指定的日志文件，其中包含所有SQL命令。当启用跟踪时，我绕过数据库初始化，

Answer 3

虽然以前的答案有效，但我发现它们存在问题，更简单的解决方案是使用NuGet中的Clutch.Diagnostics.EntityFramework软件包，该软件包在后台使用MiniProfiler。与EFTracingProvider相比，获得工作要简单得多，而且更灵活的解决方案。

该项目在GitHub上的https://github.com/Kukkimonsuta/Clutch

对于EFTracingProvider一样的功能安装的NuGet包，然后实现IDbTracingListener这样的：

using System; 
using System.Data.Common; 
using System.Diagnostics; 
using Clutch.Diagnostics.EntityFramework; 

/// <summary> 
/// 
/// </summary> 
public class DbTracingListener : IDbTracingListener 
{ 
    /// <summary> 
    /// 
    /// </summary> 
    /// <param name="connection"></param> 
    /// <param name="command"></param> 
    /// <param name="result"></param> 
    /// <param name="duration"></param> 
    public void CommandExecuted(DbConnection connection, DbCommand command, object result, TimeSpan duration) 
    { 
     Debug.WriteLine(command.CommandText); 
     Debug.WriteLine(string.Format("Executed in: {0}", duration)); 
    } 

    /// <summary> 
    /// 
    /// </summary> 
    /// <param name="connection"></param> 
    /// <param name="command"></param> 
    public void CommandExecuting(DbConnection connection, DbCommand command) 
    { 

    } 

    /// <summary> 
    /// 
    /// </summary> 
    /// <param name="connection"></param> 
    /// <param name="command"></param> 
    /// <param name="exception"></param> 
    /// <param name="duration"></param> 
    public void CommandFailed(DbConnection connection, DbCommand command, Exception exception, TimeSpan duration) 
    { 

    } 

    /// <summary> 
    /// 
    /// </summary> 
    /// <param name="connection"></param> 
    /// <param name="command"></param> 
    /// <param name="result"></param> 
    /// <param name="duration"></param> 
    public void CommandFinished(DbConnection connection, DbCommand command, object result, TimeSpan duration) 
    { 

    } 
}