joshtronic

in Software Development #PHP

How to reverse a string with PHP

Reversing a string in most languages is a pretty trivial task. In PHP we have a dedicated strrev function to do so:

$string  = 'This is my awesome string!';
$reverse = strrev($string);

But what if this function didn't exist? How would you go about reversing the string? For me, I'd loop through the string from back to forward build out a new string. You can event accomplish this a couple of different ways!

For loop with substring

$string  = 'This is how you reverse with a for loop.';
$reverse = '';
$length  = strlen($string) - 1;

for ($i = $length; $i >= 0; $i--) { $reverse .= substr($string, $i, 1); }

String to array

$string  = 'This is how you reverse with a for loop.';
$string  = str_split($string);

krsort($string);

$reverse = implode('', $string);