Difference between finialize, destructor and dispose

All classes which implement the IDisposable interface need a Dispose() method. It is only really necessary to implement this interface if your class has references to unmanaged resources (file handles, database connections etc) which need to be released as soon as possible when the object is no longer needed.

You can call Dispose() either directly or implicitly with the 'using' statement. It doesn't actually destroy the managed object which will be done in due course by the garbage collector when there are no longer any references to it. After calling Dispose(), it's therefore best to set the reference to the object to null so you can't access it again by mistake as it may be in an unstable state.

Finalization is the stage when the garbage collector is about to destroy the object and reclaim the memory it is using on the managed heap. If the object has a Finalize() method, then this is called first by the system to provide any final clean up that may be needed - for example if you've failed to call Dispose() already on an IDisposable object.

In C#, the Finalize() method is represented by destructor syntax - the compiler simply translates the latter to the former.