PHP - what is the function to turn $ sign to %24 or any other special character?

Question

htmlspecialchars won't do it and neither does htmlentities.

Answer 1

urlencode()

Returns a string in which all non-alphanumeric characters except -_. have been replaced with a percent (%) sign followed by two hex digits and spaces encoded as plus (+) signs. It is encoded the same way that the posted data from a WWW form is encoded, that is the same way as in application/x-www-form-urlencoded media type. This differs from the » RFC 1738 encoding (see rawurlencode()) in that for historical reasons, spaces are encoded as plus (+) signs.

http://php.net/urlencode

Answer 2

urlencode?

Answer 3

urlencode()

docs