Thread類線程經常使用操做

建立線程

線程是經過擴展 Thread 類建立的。擴展的 Thread 類調用 Start() 方法來開始子線程的執行。

下面的程序演示了這個概念：

class ThreadCreationProgram
    {
        public static void CallToChildThread()
        {
            Console.WriteLine("Child thread starts");
        }
       
        static void Main(string[] args)
        {
            ThreadStart childref = new ThreadStart(CallToChildThread);
            Console.WriteLine("In Main: Creating the Child thread");
            Thread childThread = new Thread(childref);
            childThread.Start();
            Console.ReadKey();
        }
    }

當上面的代碼被編譯和執行時，它會產生下列結果：

In Main: Creating the Child thread
Child thread starts

管理線程

Thread 類提供了各類管理線程的方法。

下面的實例演示了 sleep() 方法的使用，用於在一個特定的時間暫停線程。

class ThreadCreationProgram
    {
        public static void CallToChildThread()
        {
            Console.WriteLine("Child thread starts");
            // 線程暫停 5000 毫秒
            int sleepfor = 5000;
            Console.WriteLine("Child Thread Paused for {0} seconds",
                              sleepfor / 1000);
            Thread.Sleep(sleepfor);
            Console.WriteLine("Child thread resumes");
        }
       
        static void Main(string[] args)
        {
            ThreadStart childref = new ThreadStart(CallToChildThread);
            Console.WriteLine("In Main: Creating the Child thread");
            Thread childThread = new Thread(childref);
            childThread.Start();
            Console.ReadKey();
        }
    }

當上面的代碼被編譯和執行時，它會產生下列結果：

In Main: Creating the Child thread
Child thread starts
Child Thread Paused for 5 seconds
Child thread resumes

銷燬線程

Abort() 方法用於銷燬線程。

經過拋出 threadabortexception 在運行時停止線程。這個異常不能被捕獲，若是有 finally 塊，控制會被送至 finally 塊。

下面的程序說明了這點：

class ThreadCreationProgram
    {
        public static void CallToChildThread()
        {
            try
            {

                Console.WriteLine("Child thread starts");
                // 計數到 10
                for (int counter = 0; counter <= 10; counter++)
                {
                    Thread.Sleep(500);
                    Console.WriteLine(counter);
                }
                Console.WriteLine("Child Thread Completed");

            }
            catch (ThreadAbortException e)
            {
                Console.WriteLine("Thread Abort Exception");
            }
            finally
            {
                Console.WriteLine("Couldn't catch the Thread Exception");
            }

        }
       
        static void Main(string[] args)
        {
            ThreadStart childref = new ThreadStart(CallToChildThread);
            Console.WriteLine("In Main: Creating the Child thread");
            Thread childThread = new Thread(childref);
            childThread.Start();
            // 中止主線程一段時間
            Thread.Sleep(2000);
            // 如今停止子線程
            Console.WriteLine("In Main: Aborting the Child thread");
            childThread.Abort();
            Console.ReadKey();
        }
    }

當上面的代碼被編譯和執行時，它會產生下列結果：

In Main: Creating the Child thread
Child thread starts
0
1
2
In Main: Aborting the Child thread
Thread Abort Exception
Couldn't catch the Thread Exception