Question

Is there an easy way in javascript to only escape certain ranges of control characters?

Specifically, I want to escape just the ranges “\x00-\x1f” and “\x7f-\xff” (control and high-bit characters). I need to escape only those characters before calculating a hash that is then sent to an API. The standard functions like encodeURI() and escape() escape too much.

Basically, I need to match the functionality of perl’s uri_escape($text,”\x00-\x1f\x7f-\xff”) .

Answer 1

function uri_escape( text, re ) {

    function pad( num ) {
        return num.length < 2 ? "0" + num : num;
    }

    return text.replace( re, function(v){
        return "%"+pad(v.charCodeAt(0).toString(16)).toUpperCase();
    });
}

uri_escape( "\u0015\u0012", /[\x00-\x1f\x7f-\xff]/g );
//"%15%12"