This is a question you can read everywhere on the web with various answers :
$ext = end(explode('.', $filename));
$ext = substr(strrchr($filename, '.'), 1);
$ext = substr($filename, strrpos($filename, '.') + 1);
$ext = preg_replace('/^.*\.([^.]+)$/D', '$1', $filename);
$exts = split("[/\\.]", $filename);
$n = count($exts)-1;
$ext = $exts[$n];
etc.
However, there is always "the best way" and it should be on stackoverflow.
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pathinfo - http://uk.php.net/manual/en/function.pathinfo.php
An example...
$path_info = pathinfo('/foo/bar/baz.bill'); echo $path_info['extension']; // "bill"vaske : This one is "the best way"From Adam Wright -
People from other scripting languages always think theirs is better because they have a built in function to do that and not PHP (I am looking at pythonistas right now :-)).
In fact, it does exist, but few people know it. Meet pathinfo :
$ext = pathinfo($filename, PATHINFO_EXTENSION);This is fast, efficient, reliable and built in. Pathinfo can give you others info, such as canonical path, regarding to the constant you pass to it.
Enjoy
J-P : Why didn't you just put the answer in the question!?e-satis : Because it's written is the overflow FAQ do it this way.Mark Biek : I wish I could vote this up twice. I can't tell you how much code I've been able to replace using pathinfoe-satis : So do I. That's why I put it here !From e-satis -
E-satis response is the correct way to determine the file extension.
Alternatively, instead of relying on a files extension, you could use the fileinfo (http://us2.php.net/fileinfo) to determine the files MIME type.
Here's a simplified example of processing an image uploaded by a user:
// Code assumes necessary extensions are installed and a successful file upload has already occurred // Create a FileInfo object $finfo = new FileInfo(null, '/path/to/magic/file'); // Determine the MIME type of the uploaded file switch ($finfo->file($_FILES['image']['tmp_name'], FILEINFO_MIME) { case 'image/jpg': $im = imagecreatefromjpeg($_FILES['image']['tmp_name']); break; case 'image/png': $im = imagecreatefrompng($_FILES['image']['tmp_name']); break; case 'image/gif': $im = imagecreatefromgif($_FILES['image']['tmp_name']); break; }From Toxygene
