private function RegExp_FileExt($FileExts) {
		/*
		Purpose
			Used to create a regular expression to match a specified list of file extensions.
		Parameters
			FileExts (Arr) = A list of file extensions we're working with.
				Elements in this list should not contain leading periods.
		Return (String)
			Returns a regular expression that matches all of the file suffixes in the specified list (FileExt).
		Version History
			1.0 8/11/2008 by Russ Tanner (russ@herballure.com)
		*/

		return '/^.*\.(' . implode('|', $FileExts) . ')$/';

	}