Microsoft Certified Solutions Developer (MCSD) Certification Practice Test

What statement is equivalent to using the "lock" keyword in C#?

1. Monitor.TryEnter and Monitor.TryExit

2. Monitor.Enter and Monitor.Exit

3. SyncLock and End SyncLock

4. Lock.Enter and Lock.Exit

The correct answer is: Monitor.Enter and Monitor.Exit

The statement that is equivalent to using the "lock" keyword in C# is the one involving Monitor.Enter and Monitor.Exit. When you use the "lock" statement, it implicitly utilizes the Monitor class to manage access to critical sections of code, ensuring that only one thread can execute that section at a time. Specifically, when the lock is acquired, the Monitor.Enter method is called, and when the lock is released, the Monitor.Exit method is invoked. This mechanism is fundamental for thread safety, preventing race conditions by ensuring that only one thread can access the locked resource or perform the locked action at a time. The "lock" statement abstracts this process into a simpler syntax, but it fundamentally works through the Monitor class. The other choices involve either differing constructs that do not directly map to the behavior of the "lock" statement in C# or incorrect methods. For example, SyncLock and End SyncLock are related to Visual Basic, not C#. Thus, the rationale behind using Monitor.Enter and Monitor.Exit aligns perfectly with the function and purpose served by the "lock" keyword in C#.