The return value of strtolower can be passed as the third argument to str_replace (where $string is present). The str_replace function is used to replace a set of characters/character with a different set of character/string.
Example
$str = 'hello have a good day everyone';
echo str_replace(' ', '-', strtolower($str));Output
This will produce the following output −
hello-have-a-good-day-everyone