How to get a file’s extension in PHP?

This is a question you can read everywhere on the web with various answers:

solution 1

People from other scripting languages always think theirs is better because they have a built-in function to do that and not PHP.

In fact, it does exist, but few people know it. Meet pathinfo():

$ext = pathinfo($filename, PATHINFO_EXTENSION);

This is fast and built-in. pathinfo() can give you other information, such as canonical path, depending on the constant you pass to it.

If you want to be able to deal with non-ASCII characters, you need to set the locale first. E.G:

setlocale(LC_ALL,'en_US.UTF-8');

Note: This doesn’t take into consideration the file content or mime type, you only get the extension. But it’s what you asked for.