Use this one to decode the strings encoded with base64_encode() (or any string encoded with MIME base64).

Set the second parameter to true and it will return false should it encounter any characters outside the base64 alphabet. Otherwise, set to false (default) those characters are ignored.

$new = base64_decode( 'TW9ua2V5' );       // Monkey
$new = base64_decode( 'TW9ua2V5', true ); // Monkey
$new = base64_decode( '^TW9ua2V5' );      // Monkey
$new = base64_decode( '^TW9ua2V5', true ); // false