多线程同步问题解决方法之一---使用lock

   1: using System;

   2: using System.Collections.Generic;

   3: using System.Linq;

   4: using System.Text;

   5: using System.Threading;

   6: using System.Threading.Tasks;

   7:  

   8: namespace SynchronizationSamples

   9: {

  10:     public class SharedState

  11:     {

  12:         private int state = 0;

  13:         private object syncRoot = new object();

  14:         public int State 

  15:         { 

  16:             get{return state;}

  17:             set { state = value; }

  18:         }

  19:  

  20:         public int IncrementState()

  21:         {

  22:             lock (syncRoot)

  23:             {

  24:                 return ++state;

  25:             }

  26:             

  27:         }

  28:     }

  29:  

  30:     public class Job

  31:     {

  32:         SharedState sharedState;

  33:         public Job(SharedState sharedState)

  34:         {

  35:             this.sharedState = sharedState;

  36:         }

  37:  

  38:         public void DoTheJob()

  39:         {

  40:             for (int i = 0; i < 50000;i++ )

  41:             {

  42:                 lock (sharedState)

  43:                 {

  44:                     sharedState.State += 1;

  45:                 }

  46:             }

  47:         }

  48:     }

  49:     class Program

  50:     {

  51:         static void Main(string[] args)

  52:         {

  53:             int numTasks = 20;

  54:             var state = new SharedState();

  55:             var tasks = new Task[numTasks];

  56:  

  57:             for (int i = 0; i < numTasks; i++)

  58:             {

  59:                 tasks[i] = new Task(new Job(state).DoTheJob);

  60:                 tasks[i].Start();

  61:             }

  62:  

  63:             for (int i = 0; i < numTasks;i++ )

  64:             {

  65:                 tasks[i].Wait();

  66:             }

  67:             Console.WriteLine("summarized {0}",state.State);

  68:             Console.Read();

  69:         }

  70:     }

  71: }