- source is the original to decode
Returns the "normal" version of the supplied source string with all URI-encoded escape sequences replaced with non-alphanumeric characters. For example, "+" characters are replaced with spaces and all instances of "%" followed by a two-digit (hexadecimal) character code are replaced with their corresponding non-alphanumeric characters.
See the w3c page here for more info.
String converted by this function can be returned to their original form with url_encode().