The .fromCharCode()
function takes a number, not a string. You can’t put together a string like that and expect the parser to do what you think it’ll do; that’s just not the way the language works.
You could ammend your code to make a string (without the ‘\u’) from your hex number, and call
var n = parseInt(hexString, 16);
to get the value. Then you could call .fromCharCode()
with that value.