When user input space or nothing in the input bar, a plus sign + is still passed to my php backend. I would want to remove all plus signs before and after a word (e.g. return 'school' from '+++school++"). I see php have some nice function like strip_tag, but I am not sure what I should use in this case. Or is there a way to configure it (maybe through javascript?) so that those meaningless space/+ wouldn't even enter into the query string?
You can use:
$input = trim(urldecode($input));
where $input is one of the post parameters, such as: $input = $_POST["query"]; // if query was the POST parameter.
Edit: The other advantage of using urldecode is that it takes care of all other non alphanumeric characters that have been encoded.
$str = '++school++';
return trim(urldecode($str)
The + in the query string becomes a space in $_GET. All you need to do is trim leading and trailing spaces.
trim($_GET['param'])