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使用EntityFramework6.1的DbCommandInterceptor拦截生成的SQL语句

时间：2016-06-04 00:36:12 阅读：408 评论：0 收藏：0 [点我收藏+]

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EF6.1也出来不少日子了,6.1相比6.0有个很大的特点就是新增了System.Data.Entity.Infrastructure.Interception 命名空间,此命名空间下的对象可以允许我们更加方便的了解到EF运行时的一些信息,当然我们最想看的还是EF生成的Sql语句,话不多讲,开始干吧;

class EFIntercepterLogging : DbCommandInterceptor
{
private readonly Stopwatch _stopwatch = new Stopwatch();
public override void ScalarExecuting(System.Data.Common.DbCommand command, DbCommandInterceptionContext<object> interceptionContext)
{
base.ScalarExecuting(command, interceptionContext);
_stopwatch.Restart();
}
public override void ScalarExecuted(System.Data.Common.DbCommand command, DbCommandInterceptionContext<object> interceptionContext)
{
_stopwatch.Stop();
if (interceptionContext.Exception != null)
{
Trace.TraceError("Exception:{1} \r\n --> Error executing command: {0}", command.CommandText, interceptionContext.Exception.ToString());
}
else
{
Trace.TraceInformation("\r\n执行时间:{0} 毫秒\r\n-->ScalarExecuted.Command:{1}\r\n", _stopwatch.ElapsedMilliseconds, command.CommandText);
}
base.ScalarExecuted(command, interceptionContext);
}
public override void NonQueryExecuting(System.Data.Common.DbCommand command, DbCommandInterceptionContext<int> interceptionContext)
{
base.NonQueryExecuting(command, interceptionContext);
_stopwatch.Restart();
}
public override void NonQueryExecuted(System.Data.Common.DbCommand command, DbCommandInterceptionContext<int> interceptionContext)
{
_stopwatch.Stop();
if (interceptionContext.Exception != null)
{
Trace.TraceError("Exception:{1} \r\n --> Error executing command:\r\n {0}", command.CommandText, interceptionContext.Exception.ToString());
}
else
{
Trace.TraceInformation("\r\n执行时间:{0} 毫秒\r\n-->NonQueryExecuted.Command:\r\n{1}", _stopwatch.ElapsedMilliseconds, command.CommandText);
}
base.NonQueryExecuted(command, interceptionContext);
}
public override void ReaderExecuting(System.Data.Common.DbCommand command, DbCommandInterceptionContext<System.Data.Common.DbDataReader> interceptionContext)
{
base.ReaderExecuting(command, interceptionContext);
_stopwatch.Restart();
}
public override void ReaderExecuted(System.Data.Common.DbCommand command, DbCommandInterceptionContext<System.Data.Common.DbDataReader> interceptionContext)
{
_stopwatch.Stop();
if (interceptionContext.Exception != null)
{
Trace.TraceError("Exception:{1} \r\n --> Error executing command:\r\n {0}", command.CommandText, interceptionContext.Exception.ToString());
}
else
{
Trace.TraceInformation("\r\n执行时间:{0} 毫秒 \r\n -->ReaderExecuted.Command:\r\n{1}", _stopwatch.ElapsedMilliseconds, command.CommandText);
}
base.ReaderExecuted(command, interceptionContext);
}
}

上面这段代码需要命名空间:

using System.Data.Entity.Infrastructure.Interception;
using System.Diagnostics;

从方法名我们可以看出大致就三类:读取类的sql,[Reader],非读取类的sql,[NonQuery],还有[Scalar],这类用的比较少,跟原始的ADO.NET命令类型基本一样,不多讲.每个sql语句类型的方法都有执行前Executing,执行后Executed,从命名上我们就可以看出AOP的身影哈,接下来看如何使用它...

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