preg_replace all spaces

Question

I\'m trying to replace all spaces with underscores and the following is not working:

$id = \"aa aa\";
echo $id;
preg_replace(\'/\\s+/\', \'_\', $id);
echo $i         


        

Answer 1

You have forgotten to assign the result of preg_replace into your $id

$id = preg_replace('/\s+/', '_', $id);