Check if NSURL is Local File

There is -isFileReferenceURL as of iOS 5 that checks if the url is an file reference. Before 5.0, it did nothing according to the documentation..

Available in iOS 5.0 and later. (Symbol is present in iOS 4, but performs no operation.)

I hope this helps the new-comers...

The -isFileURL will check if your URL uses the file: scheme. It doesn't check whether it's referencing an actual file.