using (var reader = XmlReader.Create(File.Open(fileName, FileMode.Open)))
    { ... }

You probably wonder what’s the problem of the code printed above. I don’t see it too, however, I know there is a problem related to this code. The problem lies in the Create overload used in the example code. It uses default XmlReaderSettings. Unfortunately, this settings do not include having the CloseInput property set to true. You can do the math: no closed file at all! That’s a guarantee for having troubles on the file ‘being in use already’.

The solution to this problem is quite simple:

using (XmlReader reader = XmlReader.Create(File.Open(path, FileMode.Open),
         new XmlReaderSettings { CloseInput = true })) { ... }

How can we call this? A ‘bug’? No, at least not technically spoken. Since the XmlReader creates the stream, it should close it too. The case is, you should not expext it knowing the using statement as most people know it (fail-proofing your code). Since I know this, I am a little bit scared about using using statements without calling the stream’s constructor. You can do so, but be sure it does what you expect it to do… In my opinion, the using statement still remains very helpful, please I do not consider it being as perfect as I thought it to be for years …

Trying to solve the bug, I  found the following attribute to be the problem: [ToolboxItem(true)]. Just delete the attribute, rebuild the application and the problem/bug disappears!

Good luck! Happy coding!