String from hex without encoding

Question

I have a string that contains hex values, something like: "1BB3AE3E".

Now I would like to convert this to a string (expected result "≥Æ>") of exactly that byte representation (so written to a file, and opened with hex viewer would show "1BB3AE3E")

This is something like Ruby's

['1BB3AE3E'].pack('H*')

I have tried creating Buffer.toString, String.fromCharCode, but it didn't work as I expected. The closes I got to the result was with

var input = "1BB3AE3E"
var buffer = new Buffer(input, "hex")
var result = buffer.toString("binary")

and it resulted with a file containing "³®>" for which hex is: 1B C2 B3 C2 AE 3E. Where those C2 are coming from? How can I make it work?

I've also tried

var hexes = this.match(/.{1,2}/g) || [];
var back = "";
for(j = 0; j< hexes.length; j++) {
    back += String.fromCharCode(parseInt(hexes[j], 16));
}

but to no vain. The effect is as above.

Answer 1

//var result= parseInt(buffer, 16).toString(2)
  var result= parseInt(input, 16).toString(2)

Output:"11011101100111010111000111110"

also see: https://gist.github.com/faisalman/4213592

Answer 2

For do a good code you should be hexDecode and the protoype and fromCharCode and parseInt, you can do for examples:

String.prototype.hexDecode = function(){
    var j;
    var hexes = this.match(/.{1,4}/g) || [];
    var back = "";
    for(j = 0; j<hexes.length; j++) {
        back += String.fromCharCode(parseInt(hexes[j], 16));
    }

    return back;
}