Question

Some users like to write post title all in uppercase, which is completely annoying. Instead of asking them to write it again I want to know what percentage of the title they wrote is uppercase so that if they exceed 50% I just apply strtolower.

My idea is to turn their string to lowercase and see how different it is from the original string (3 different characters would mean originally there were 3 uppercase characters):

$title = 'AAAA';
$title2 =  strtolower($title);

How do I compare $title with $title2 to get the number of characters that don’t match?

Eg:

$title = 'AAAa'
$title2 = 'aaaa'

$differences = '3';

Answer 1

$title = 'AAAa';
$title2 =  strtolower($title);
$differences = 0;
for ($i=0,$l=strlen($title); $i < $l; $i++) {
  if ($title{$i} !== $title2{$i}) {
    $differences++;
  }
}