strtr()
strtr() is a PHP native function that translates characters or replaces substrings in a string.
It has two signatures. With three arguments, strtr($string, $from, $to), it replaces each character found in $from with the character at the same position in $to. Both strings must have the same length; extra characters in the longer one are ignored.
With two arguments, strtr($string, $replace_pairs), it takes an array mapping substrings to their replacements. Unlike str_replace(), strtr() replaces the longest matching keys first and does not rescan replaced text, which avoids double substitutions.
strtr() is often faster than multiple chained str_replace() calls when doing several substitutions at once.
<?php
echo strtr('Hello World', 'ol', '0L'); // HeLL0 W0rLd
$trans = ['Hello' => 'Hi', 'World' => 'Earth'];
echo strtr('Hello World', $trans); // Hi Earth
// Longest keys are matched first
$trans = ['a' => 'X', 'ab' => 'Y'];
echo strtr('ab', $trans); // Y, not XB
?>