创建线程
线程是通过扩展 Thread 类创建的。扩展的 Thread 类调用 Start() 方法来开始子线程的执行。
下面的程序演示了这个概念:
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(); } }
当上面的代码被编译和执行时,它会产生下列结果:
In Main: Creating the Child thread
Child thread starts
管理线程
Thread 类提供了各种管理线程的方法。
下面的实例演示了 sleep() 方法的使用,用于在一个特定的时间暂停线程。
class ThreadCreationProgram { public static void CallToChildThread() { Console.WriteLine("Child thread starts"); // 线程暂停 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(); } }
当上面的代码被编译和执行时,它会产生下列结果:
In Main: Creating the Child thread Child thread starts Child Thread Paused for 5 seconds Child thread resumes
销毁线程
Abort() 方法用于销毁线程。
通过抛出 threadabortexception 在运行时中止线程。这个异常不能被捕获,如果有 finally 块,控制会被送至 finally 块。
下面的程序说明了这点:
class ThreadCreationProgram { public static void CallToChildThread() { try { Console.WriteLine("Child thread starts"); // 计数到 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(); // 停止主线程一段时间 Thread.Sleep(2000); // 现在中止子线程 Console.WriteLine("In Main: Aborting the Child thread"); childThread.Abort(); Console.ReadKey(); } }
当上面的代码被编译和执行时,它会产生下列结果:
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