C#線程間同步處理操作之共享同步變量

在應用程序開發過程中，常常需要同步類操作。本文介紹使用lock方法，用共享變量的形式來實現線程間同步操作。

 public class SyncTest
    {
        private object syncstate = new object();
        private int num = 0;
        public void Encrement()
        {
            lock (syncstate)
            {
                for (int i = 0; i < 1000; i++)
                {
                    num++;
                    Console.WriteLine("Current Thread {0} num = {1};",Thread.CurrentThread.ManagedThreadId, num);
                }
                 
            }
        }
    }

 public class SampleSync
    {
       public void task(object obj)
       {
           SyncTest o = obj as SyncTest;
           o.Encrement();
       }
    }

 public void Encrement()
         {
              int num = 0;
              SyncTest s = new SyncTest();
             for (int i = 0; i < 10;i++ )
             {

                 Task.Run(() => {
                     new SampleSync().task(s);
                 });
                
             }
             Thread.Sleep(1000*10);
         }

 

結果實現瞭如下：

Current Thread 24 num = 1995;
Current Thread 24 num = 1996;
Current Thread 24 num = 1997;
Current Thread 24 num = 1998;
Current Thread 24 num = 1999;
Current Thread 24 num = 2000;
Current Thread 14 num = 2001;
Current Thread 14 num = 2002;
Current Thread 14 num = 2003;

結論：

1.首先在共享的類中聲明 private object syncstate = new object();注意，當類作爲唯一傳入的實例類，纔能有效控制併發訪問。如果每傳入一個對象，都是新的對象，即無效。

2.在多個線程啓動之前，得到同步對象的實例。

3.傳入該對象。