What's the best way/practice to get the extension of a uploaded file in PHP [duplicate]

Question

I have a form that allow users to upload files, I however need to get the file extension, which I am able to get, but not sure if I'm using the most effective solution

I can get it using the following ways

$fileInfo = pathinfo($_FILES['File']['name']);
echo $fileInfo['extension'];

$ext = end(explode('.',$_FILES['File']['name']));
echo $ext;

Which method is the best to use or are there even better solutions that would get the extension?

Answer 1

pathinfo($_FILES['File']['name'], PATHINFO_EXTENSION)

• Use a built-in function whenever possible (what @Sarfraz said in the meantime), and
• Extract only the needed information (options = PATHINFO_EXTENSION)

Answer 2

Better way - fileinfo extension with PHP >=5.3

PS: do not trust file name extension, any user can any how rename the file extension