Question

I have 2 threads that communicate by sending files to each other. When Thread #1 does a

// Thread #1
File.Create(@"C:\somedir\response.done");

Then Thread #2 is supposed to delete it.

// Thread #2
while (!File.Exists(@"C:\somedir\response.done"))
    Thread.Sleep(100);


while (File.Exists(@"C:\somedir\response.done"))
    {
        try {
               File.Delete(@"C:\somedir\response.done");
            }
        catch { Thread.Sleep(1000); };

    }

However, the file seems to be locked. There is generated a response.done file in the directory, but it is never deleted. When I try to manually remove it, then

“The action cannot be completed because the file is open in MyProgram. Close the file and try again.”

How can I avoid this?

Answer 1

File.Create returns a FileStream. So… close it:

using(File.Create(path)) {
    // add contents here if needed
}

The using ensures it is Dispose()d, hence closed. Note: it is also possible that some AV systems will interfere with file access, but that is usually not a huge problem.