请参考下面的链接，它解释了为什么锁(这)不是一个好主意。

https://learn.microsoft.com/en-us/dotnet/standard/threading/managed-threading-best-practices

所以解决方案是添加一个私有对象，例如，lockObject到类中，并将代码区域放在lock语句中，如下所示:

lock (lockObject)
{
...
}

这里也有一些关于这个的很好的讨论:这是互斥锁的正确使用吗?

这里有一个更简单的例子(来自这里的问题34)，为什么锁(this)是不好的，并且当你的类的消费者也试图锁定对象时可能会导致死锁。 下面，三个线程中只有一个线程可以继续，其他两个线程处于死锁状态。

class SomeClass { public void SomeMethod(int id) { **lock(this)** { while(true) { Console.WriteLine("SomeClass.SomeMethod #" + id); } } } } class Program { static void Main(string[] args) { SomeClass o = new SomeClass(); lock(o) { for (int threadId = 0; threadId < 3; threadId++) { Thread t = new Thread(() => { o.SomeMethod(threadId); }); t.Start(); } Console.WriteLine(); }

为了解决这个问题，这家伙使用了Thread。TryMonitor(带超时)而不是lock:

班长。TryEnter(temp, millisecondsTimeout, ref lockWasTaken); 如果(lockWasTaken) ｛ doAction (); ｝ 其他的 ｛ 抛出新的异常(" cannot get lock"); ｝

https://blogs.appbeat.io/post/c-how-to-lock-without-deadlocks

.．.同样的论点也适用于这个结构:

lock(typeof(SomeObject))

以下是一些更容易遵循的示例代码(IMO):(将在LinqPad中工作，参考以下名称空间:System。Net和System.Threading.Tasks)

需要记住的一点是，lock(x)基本上是语法糖，它所做的就是使用Monitor。输入，然后使用try、catch和finally块调用Monitor.Exit。参见:https://learn.microsoft.com/en-us/dotnet/api/system.threading.monitor.enter(备注部分)

或者使用c#锁语句(Visual Basic中的SyncLock语句)， 它将Enter和Exit方法包装在一个try…finally块中。

void Main()
{
    //demonstrates why locking on THIS is BADD! (you should never lock on something that is publicly accessible)
    ClassTest test = new ClassTest();
    lock(test) //locking on the instance of ClassTest
    {
        Console.WriteLine($"CurrentThread {Thread.CurrentThread.ManagedThreadId}");
        Parallel.Invoke(new Action[]
        {
            () => {
                //this is there to just use up the current main thread. 
                Console.WriteLine($"CurrentThread {Thread.CurrentThread.ManagedThreadId}");
                },
            //none of these will enter the lock section.
            () => test.DoWorkUsingThisLock(1),//this will dead lock as lock(x) uses Monitor.Enter
            () => test.DoWorkUsingMonitor(2), //this will not dead lock as it uses Montory.TryEnter
        });
    }
}

public class ClassTest
{
    public void DoWorkUsingThisLock(int i)
    {
        Console.WriteLine($"Start ClassTest.DoWorkUsingThisLock {i} CurrentThread {Thread.CurrentThread.ManagedThreadId}");
        lock(this) //this can be bad if someone has locked on this already, as it will cause it to be deadlocked!
        {
            Console.WriteLine($"Running: ClassTest.DoWorkUsingThisLock {i} CurrentThread {Thread.CurrentThread.ManagedThreadId}");
            Thread.Sleep(1000);
        }
        Console.WriteLine($"End ClassTest.DoWorkUsingThisLock Done {i}  CurrentThread {Thread.CurrentThread.ManagedThreadId}");
    }

    public void DoWorkUsingMonitor(int i)
    {
        Console.WriteLine($"Start ClassTest.DoWorkUsingMonitor {i} CurrentThread {Thread.CurrentThread.ManagedThreadId}");
        if (Monitor.TryEnter(this))
        {
            Console.WriteLine($"Running: ClassTest.DoWorkUsingMonitor {i} CurrentThread {Thread.CurrentThread.ManagedThreadId}");
            Thread.Sleep(1000);
            Monitor.Exit(this);
        }
        else
        {
            Console.WriteLine($"Skipped lock section!  {i} CurrentThread {Thread.CurrentThread.ManagedThreadId}");
        }

        Console.WriteLine($"End ClassTest.DoWorkUsingMonitor Done {i} CurrentThread {Thread.CurrentThread.ManagedThreadId}");
        Console.WriteLine();
    }
}

输出

CurrentThread 15
CurrentThread 15
Start ClassTest.DoWorkUsingMonitor 2 CurrentThread 13
Start ClassTest.DoWorkUsingThisLock 1 CurrentThread 12
Skipped lock section!  2 CurrentThread 13
End ClassTest.DoWorkUsingMonitor Done 2 CurrentThread 13

注意线程#12永远不会因为死锁而结束。

如果可以公开访问实例，就会出现问题，因为可能有其他请求正在使用相同的对象实例。最好使用私有/静态变量。