Synchronization with the Monitor Class

The System.Threading.Monitor class is the support object for the SyncLock..End SyncLock statement, and the compiler translates SyncLock blocks into invocations to the Monitor class. You use it as follows:

Basically Monitor.Enter locks the object whereas Monitor.Exit unlocks it. It is fundamental to place Monitor.Exit in the Finally part of the Try..Catch block so that resources will be unlocked anyway. At this point you might wonder why use Monitor instead of SyncLock..End SyncLock because they produce the same result. The difference is that Monitor also exposes additional members, such as the TryEnter method that supports timeout, as demonstrated here:

Monitor.TryEnter(lockObject, 3000, result)

This code attempts to obtain the lock on the specified object for three seconds before terminating.