The following two functions perform the '%'-substitution for characters that may otherwise be interpreted as metacharacters.
According to: RFC 1738, RFC 1630
plus: This option has been added because there are some
escape function. The default is
true because this is the RFC-
plus: Whether '+' is converted to space. The default is true. If false, '+' is returned as it is.
The optional arguments
len may restrict the string
to process to this substring.
plus: Whether spaces are converted to '+'. The default is true. If false, spaces are converted to "%20", and only %xx sequences are produced.
The following two functions create and analyze URL-encoded parameters.