实体框架4.1 - EFTracingProvider

可以。我正在使用社区版本的数据库优先DbContexts和代码优先DbContexts。这个答案是基于项目网站上的一个讨论线程。

对于数据库优先/设计器DbContexts(通过ADO。. NET DbContext生成器模板)，您可以简单地添加以下构造函数:

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

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

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;
    }
}

虽然前面的答案有效，但我发现它们存在问题，一个更简单的解决方案是使用NuGet中的Clutch.Diagnostics.EntityFramework包，该包在幕后使用MiniProfiler。它比EFTracingProvider要简单得多，而且是一个更灵活的解决方案。

项目在GitHub上https://github.com/Kukkimonsuta/Clutch

对于EFTracingProvider之类的功能，安装NuGet包，然后像这样实现IDbTracingListener:

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)
    {
    }
}

如果您正在使用DBContext和MVC Model First，这意味着使用EntityConnections，那么下面的示例代码应该是您所需要的:

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

:

In the Web。在配置文件中添加以下部分:

  <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>

:

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

不需要包含ExtendedEntities或原始文章中提到的其他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，我绕过了数据库初始化，