XPath/XQuery escape-html-uri function


Escapes a URI in the same way that HTML user agents handle attribute values expected to contain URIs.


$uri as xs:string?
) as xs:string


This function is deterministic, context-independent, and focus-independent.


If $uri is the empty sequence, the function returns the zero-length string.

Otherwise, the function escapes all characters except printable characters of the US-ASCII coded character set, specifically the codepoints between 32 and 126 (decimal) inclusive. Each character in $uri to be escaped is replaced by an escape sequence, which is formed by encoding the character as a sequence of octets in UTF-8, and then representing each of these octets in the form %HH, where HH is the hexadecimal representation of the octet. This function must always generate hexadecimal values using the upper-case letters A-F.


The expression fn:escape-html-uri("http://www.example.com/00/Weather/CA/Los Angeles#ocean") returns "http://www.example.com/00/Weather/CA/Los Angeles#ocean".

The expression fn:escape-html-uri("javascript:if (navigator.browserLanguage == 'fr') window.open('http://www.example.com/~bébé');") returns "javascript:if (navigator.browserLanguage == 'fr') window.open('http://www.example.com/~b%C3%A9b%C3%A9');".


The behavior of this function corresponds to the recommended handling of non-ASCII characters in URI attribute values as described in Appendix B.2.1.