Change file extension

Question

How do I change a files file-extension name in PHP?

For example: $filename=\'234230923_picture.bmp\' and I want the extension to change to jpg

Answer 1

Not using regex (like the basename example), but allowing multiple extension possibilities (like the regex example):

$newname = str_replace(array(".bmp", ".gif"), ".jpg", $filename);
rename($filename, $newname);

Of course any simple replace operation, while less expensive then regex, will also replace a .bmp in the middle of the filename.

As mentioned, this isn't going to change the format of a image file. To do that you would need to use a graphics library.