How to know which processes is using a file under ASP.NET?

Question

I'm developing a multi-threaded ASP.NET 3.5 application, during working with some file, I'm getting the following exception :

The process cannot access the file because it is being used by another process

I'm looking for a way to know exactly which process is locking that file so I can stop its access to the file. OR if that is complicated, I want a way to lock the file by my thread so other threads/processes can't access it. Thanks.

Answer 1

Process Explorer will allow you to do this. Simply click "Find" -> "Find Handle or DLL", then enter the name of your file.

It will then show you every process with a handle to that file.

Answer 2

To actually lock access to the resource (the 2nd option you suggest), you could use a Mutex (a Mutual Exclusion).

I've not done any of this in .NET, but there seems to be good articles on it.