ManualResetEvent 线程同步「建议收藏」

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ManualResetEvent

ManualResetEvent 用于线程同步，通知一个或多个线程某事件已经发生。通常用于一个线程执行的任务必须在其他线程的任务执行之前完成。

ManualResetEvent状态分为两种：终止状态和非终止状态。当某一任务完成时，将ManualResetEvent设置为终止状态，这样其他等待的线程（一个或多个）将开始执行自己的任务。

注意：一旦它被终止，它将保持终止状态，直到它被手动重置。

代码示例：

<img src="http://images.cnblogs.com/OutliningIndicators/ExpandedBlockStart.gif" title="" alt="ManualResetEvent 线程同步「建议收藏」">
代码
   class  Program
 { 
  static   void  Main( string [] args)
 { 
 Caclultae calc  =   new  Caclultae();
 Console.WriteLine( " Result={0} " ,calc.result( 234 ).ToString());
 
 Console.Read();
 }
 }
  class  Caclultae
 { 
  double  baseNum,firNum,secNum,thdNum;
 AutoResetEvent[] autoEvents;
 ManualResetEvent manualEvent;
 Random Generator;
  public  Caclultae()
 { 
 autoEvents  =   new  AutoResetEvent[]
 { 
  new  AutoResetEvent( false ),
  new  AutoResetEvent( false ),
  new  AutoResetEvent( false )
 };
 manualEvent  =   new  ManualResetEvent( false );
 }
  void  CalBase( object  stateInfo)
 { 
 baseNum  =  Generator.NextDouble();
 Console.WriteLine( " BaseNum is Ok " );
 manualEvent.Set();
 }
  void  CalFirst( object  stateInfo)
 { 
  double  preCalc  =  Generator.NextDouble();
 
 manualEvent.WaitOne();
 Console.WriteLine( " FirstNum begins to Calculate " );
 firNum  =  preCalc  *  baseNum  *  Generator.NextDouble();

 autoEvents[ 0 ].Set();
 Console.WriteLine( " FirstNum Calculates successfully " );
 }
  void  CalSec( object  stateInfo)
 { 
  double  preCalc  =  Generator.NextDouble();
 manualEvent.WaitOne();
 Console.WriteLine( " SecNum begins to Calculate " );
 secNum  =  preCalc  *  baseNum  *  Generator.NextDouble();
 autoEvents[ 1 ].Set();
 Console.WriteLine( " SecNum Calculates successfully " );
 }
  void  CalThird( object  stateInfo)
 { 
  double  preCalc  =  Generator.NextDouble();
 manualEvent.WaitOne();
 Console.WriteLine( " ThrdNum begins to Calculate " );
 thdNum  =  preCalc  *  baseNum  *  Generator.NextDouble();
 autoEvents[ 2 ].Set();
 Console.WriteLine( " ThrdNum Calculates successfully " );
 }
  public   double  result( int  seed)
 { 
 Generator  =   new  Random(seed);
 ThreadPool.QueueUserWorkItem( new  WaitCallback(CalBase));
 ThreadPool.QueueUserWorkItem( new  WaitCallback(CalFirst));
 ThreadPool.QueueUserWorkItem( new  WaitCallback(CalSec));
 ThreadPool.QueueUserWorkItem( new  WaitCallback(CalThird));
 WaitHandle.WaitAll(autoEvents);
 manualEvent.Reset();
  return  firNum  +  secNum  +  thdNum;
 }
 
 }