c#之尝试锁定对象时尝试/捕获

我是多线程的新手。当对象被另一个线程锁定时，我试图锁定对象，我预计会出现错误并尝试使用 Exception，但它没有用。

class Program 
    { 
        static readonly object lockNum = new object(); 
        static int A = 10; 
 
        public static void Thread1() 
        { 
            lock (lockNum) 
            { 
                A = 100; 
                Console.WriteLine(A); 
            } 
        } 
 
        public static void Thread2() 
        { 
            Thread.Sleep(1000); 
            lock (lockNum) 
            { 
                Thread.Sleep(9000); 
                Console.WriteLine(A); 
                Console.WriteLine("Thread 2 is executed"); 
            } 
        } 
 
        public static void Thread3() 
        { 
            Thread.Sleep(3000); 
 
            try 
            { 
                lock (lockNum) 
                { 
                    Console.WriteLine(A); 
                    Console.WriteLine("Thread 3 is executed"); 
                } 
            } 
            catch (Exception ex) 
            { 
                Console.WriteLine("Object is locked"); 
            } 
 
        } 
 
    } 
 
    public class MyClass 
    { 
 
        public static void Main() 
        { 
            Thread tid1 = new Thread(new ThreadStart(Program.Thread1)); 
            Thread tid2 = new Thread(new ThreadStart(Program.Thread2)); 
            Thread tid3 = new Thread(new ThreadStart(Program.Thread3)); 
 
            tid1.Start(); 
            tid2.Start(); 
            tid3.Start(); 
 
            Console.ReadLine(); 
        } 
    } 

Thread2 和 Thread3 在 Thread.Sleep(9000); 之后一起运行，我预计 3 秒后会出现异常，因为该对象仍被 Thread2 锁定。我试图让 Thread3 再次 sleep 3 秒以检查对象是否已解锁(可能是 WriteLine 错误)并重复直到对象被解锁。

请您参考如下方法:

锁不会抛出异常，它们只是等待其他线程释放锁。

如果您想在无法领取锁时跳过代码，您可以使用

if (Monitor.TryEnter(lockNum)) 
{ 
    Console.WriteLine("No one else had the lock, now it's mine!"); 
} 
else 
{ 
    Console.WriteLine("Another thread won :("); 
} 

您可以选择为该方法提供超时。