gives the file extension for a file name.
- FileExtension["name.ext"] gives "ext".
- FileExtension gives the extension that appears after the last . in a file name.
- If there are multiple endings to a file name, separated by ., FileExtension gives only the last one.
- FileExtension gives "" if there is no file extension, if the file name has the form of a directory name, or ends with a . character.
- FileExtension ignores any directory specification.
- FileExtension by default assumes pathname separators and other conventions suitable for your operating system.
- FileExtension[…,OperatingSystem->"os"] uses the conventions of the specified operating system. Possible choices are "Windows", "MacOSX", and "Unix".
- FileExtension just operates on names of files; it does not actually search for the file specified.
- FileExtension[File["file"]] is also supported.
Introduced in 2008
(7.0)| Updated in 2016