C# Unsafe Thread Monitoring?

Question

How does the Monitoring class solve the unsafe thread problem in the following example:

class ThreadUnsafe {
		static int  val1,  val2;

static void Go(){
			if  (val2 != 0)  Console.WriteLine( val1 / val2);
                        val2=0;}
}

? · Answer

The variable val2 is not local to the function Go().  So if more than one thread calls Go you could get a division by 0. For example:
Thread 1: Does the test "if(val2 != 0)" but then it gets swapped out, and
Thread 2: Is started, calls Go(), does the if, the write, and sets val2=0.  Then Thread 2 gets swapped out and
Thread 1 is restarted, it goes to do the "Console.WriteLine(val1/val2)" but since Thread 2 set val2 to 0, it gets a divide by 0 fault.

C# Unsafe Thread Monitoring?

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