Percent-encoding and decoding

Percent-encoding, or URL encoding, is a mechanism for encoding information in a Uniform Resource Identifier (URI). Every "unsafe" character is represented in the form '%HH' or with a longer escape sequence (where H is as hexadecimal digit '0' ... 'F').

Actually, every reserved or non-ASCII (including UCS-2 or UCS-4) character

• first, is transformed into a sequence of octets using the UTF-8 or another external format transformation;
• then, the resulting sequence of octets is transformed into a string with each octet represented by an escape sequence of the form %HH.

Percent encoding is also used in the preparation of data of the application/x-www-form-urlencoded media type, as is often used in the submission of HTML form data in HTTP requests.

The '%uHHHH' escape sequences defined in MS JScript but not in RFC3986 are also recognized by the percent-decode function.

The functions described in this section are also called directly in YHTML-Template code.

• percent-encode [Function]
• percent-decode [Function]
• Encoding spaces in query

See also

• Percent encoding in Wikipedia
• YstokHTML — a library for generating and parsing HTML and XHTML documents.