In the comments to an answer I wrote we had a discussion about memory leaks and IDisposable where we didn’t come to any real conclusion.
A class that handles unmanaged resources likely implements IDisposable. If ignore that and neither call Dispose nor wraps the object in a using – will that lead to the unmanaged resource being leaked? Or will it be properly cleaned up when the GC collects the object?
We can assume that the class handling the unmanaged resource has a correct implementation of IDisposable, including finalizer etc.
It will not cause a memory leak. In fact, Dispose has absolutely nothing to do with memory management.
It will create a resource-leak. And while the GC will usually clean it up, this could be too infrequent and too late.
Omitting Dispose (
using) can slow down or even crash your App. In the case of file resources or Db connections it can even cause problems in other applications.