C# Thread.Abort方法与ThreadAbortException异常(取消线程与异常处理)

1、Abort当前线程,后续程序不会执行

class Program { public static Thread thread1; static void Main(string[] args) {
        thread1 = new Thread(Method1);
        thread1.Start();
        Console.ReadKey();
    } public static void Method1() { try { for (int i = 0; i < 10; i++)
            {
                Console.WriteLine("Mthod1: " + i.ToString());
                Thread.Sleep(1000); if (i == 3)
                {
                    Thread.CurrentThread.Abort(); // 抛出的ThreadAbortException异常 }
                Console.WriteLine("Mthod1: " + i.ToString() + " End");
            }
        } catch (SocketException ex)
        {
            Console.WriteLine("Method1 SocketException: " + ex.ToString());
        } catch (ThreadAbortException ex)
        { // ThreadAbortException要在Exception的前面,因为Exception能够匹配所有异常 Console.WriteLine("Method1 ThreadAbortException: " + ex.ToString());
        } catch (Exception ex)
        {
            Console.WriteLine("Method1 Exception: " + ex.ToString());
        } finally {
            Console.WriteLine("Method1 Finally:");
        }
    }

}


执行结果:

1、thread1.Abort()执行后会直接抛出ThreadAbortException异常。

2、异常会停止后续所有程序的执行(没有输出"Method1: 3 End")。

3、catch语句会执行。catch (Exception ex)和catch (ThreadAbortException ex)都可以捕获异常,由于Exception可以匹配所有异常,因此catch (ThreadAbortException ex)应该在catch (Exception ex)的前面使用,所以输出了“"Method1 ThreadAbortException”。

4、finally语句会执行

2、Abort当前线程,进行try catch捕获异常

class Program { public static Thread thread1; static void Main(string[] args) {
        thread1 = new Thread(Method1);
        thread1.Start();
        Console.ReadKey();
    } public static void StopMethod1() { try {
            thread1.Abort(); // 首先捕获抛出的ThreadAbortException异常 } catch (Exception ex)
        {
            Console.WriteLine("StopMethod1: " + ex.ToString());
        }
    } public static void Method1() { try { for (int i = 0; i < 10; i++)
            {
                Console.WriteLine("Mthod1: " + i.ToString());
                Thread.Sleep(1000); if (i == 5) StopMethod1(); // 再次捕获抛出的ThreadAbortException异常 }
        } catch (Exception ex)
        {
            Console.WriteLine("Method1: " + ex.ToString()); 
        }
    }        
}


运行结果:

try catch{} 捕获两次抛出的ThreadAbortException。

2、Abort当前线程,不进行try catch捕获异常

class Program { public static Thread thread1; static void Main(string[] args) {
        thread1 = new Thread(Method1);
        thread1.Start();
        Console.ReadKey();
    } public static void StopMethod1() {
        thread1.Abort();
    } public static void Method1() { for (int i = 0; i < 10; i++)
        {
            Console.WriteLine("Mthod1: " + i.ToString());
            Thread.Sleep(1000); if (i == 5) StopMethod1();
        }
    }
}


运行结果:

1、虽然线程抛出了ThreadAbortException异常,由于线程中没有使用try catch的语句捕获异常,所以看上去线程很平静的退出了。

2、而且,由于是在线程中抛出的异常,所以主进程没有任何错误提示。

3、for循环只输出到5,Abort()后一般线程会直接停止。

3、在一个线程中Abort另一个线程

class Program { public static Thread thread1; public static Thread thread2; static void Main(string[] args) {
        thread1 = new Thread(Method1);
        thread2 = new Thread(Method2);
        thread1.Start();
        thread2.Start();
        Console.ReadKey();
    } public static void StopMethod1() { try {
            thread2.Abort();
        } catch (Exception ex)
        {
            Console.WriteLine("StopMethod1: " + ex.ToString());
        }
    } public static void Method1() { try { for (int i = 0; i < 10; i++)
            {
                Console.WriteLine("Method1: " + i.ToString());
                Thread.Sleep(1000); if (i == 5) StopMethod1();
            }
        } catch (Exception ex)
        {
            Console.WriteLine("Method3: " + ex.ToString());
        }
    } public static void Method2() { try { for (int i = 0; i < 10; i++)
            {
                Console.WriteLine("Method2: " + i.ToString());
                Thread.Sleep(1000);
            }
        } catch (Exception ex)
        {
            Console.WriteLine("Method2: " + ex.ToString());
        }
    }
}


运行结果:

1、可以看到只在thread2中捕获到了ThreadAbortException异常。

2、thread1完整的运行完毕了,并且没有ThreadAbortException异常抛出。

总结

1、theadX.Abort()方法会在线程X中抛出ThreadAbortException异常,线程X中所有正在执行的try catch都会捕获该异常。

2、theadX.Abort()有可能在Y线程中调用的,不会在Y线程中抛出ThreadAbortException异常。

玩咖指针 2020-03-22 14:19:06