multithreading - Why doesn't C# allow a null value to be locked?

Question

C# doesn't allow locking on a null value. I suppose I could check whether the value is null or not before I lock it, but because I haven't locked it another thread could come along and make the value null! How can I avoid this race condition?

question from:https://stackoverflow.com/questions/7226231/why-doesnt-c-sharp-allow-a-null-value-to-be-locked

Answer 1

You cannot lock on a null value because the CLR has no place to attach the SyncBlock to, which is what allows the CLR to synchronize access to arbitrary objects via Monitor.Enter/Exit (which is what lock uses internally)