細說多線程(八) —— 計時器與鎖

     class Program
     {
         static void Main(string[] args)
         {
             ThreadPool.SetMaxThreads(1000, 1000);
 
             TimerCallback callback = new TimerCallback(ThreadPoolMessage);
             Timer t = new Timer(callback,"Hello Jack! ", 0, 1000);
             Console.ReadKey();
         }
 
         //顯示線程池現狀
         static void ThreadPoolMessage(object data)
         {
             int a, b;
             ThreadPool.GetAvailableThreads(out a, out b);
             string message = string.Format("{0}\n   CurrentThreadId is:{1}\n" +
                 "   CurrentThread IsBackground:{2}\n" +
                 "   WorkerThreads is:{3}\n   CompletionPortThreads is:{4}\n",
                  data + "Time now is " + DateTime.Now.ToLongTimeString(),
                  Thread.CurrentThread.ManagedThreadId,
                  Thread.CurrentThread.IsBackground.ToString(),
                  a.ToString(), b.ToString());
             Console.WriteLine(message);
         }
     }

1 private void Method()
2 {
3       lock(this)
4       {
5           //在此進行的操作能保證在同一時間內只有一個線程對此對象操作
6       }
7 }

 class Control
 {
       private object obj=new object();
       
       public void Method()
       {
             lock(obj)
             {.......}
       }
 }

 1 class Control
 2 {
 3       private object obj=new object();
 4  
 5       public void Method()
 6       {
 7             Monitor.Enter(obj);
 8             try
 9             {......}
10             catch(Excetion ex)
11             {......}
12             finally
13             {
14                 Monitor.Exit(obj);
15             }
16       }
17 }
18          

 class Example
 {
       private int a=1;
 
       public void AddOne()
       {
              int newA=Interlocked.Increment(ref a);
       }
 }

1 public void SetData()
2 {
3       Interlocked.Exchange(ref a,100);
4 }

 public void CompareAndExchange()
 {
     Interlocked.CompareExchange(ref a,100,1);
 }