How PHP obtains file extensions from a given URL

The example in this article describes how PHP obtains the file name extension from a given URL. Share to everyone for your reference. The implementation methods are as follows:

<?php
/**
 * Given URL, get file suffix
 * @param string $url
 * @return string
/function Geturlpostfix ($ URL)
{
  $url _arr = Explode ('. ', $url);
  $postfix = $url _arr[count ($url _arr)-1];
  $substr = substr ($postfix, 0, 3);
  return $substr;
}
$url = "http://www.bitsCN.com/index.html?id=1";
$str = Geturlpostfix ($url);
Echo $str. "N";

I hope this article will help you with your PHP program design.