Javascript ArrayBuffer to Hex

Question

I\'ve got a Javascript ArrayBuffer that I would like to be converted into a hex string.

Anyone knows of a function that I can call or a pre written function already

Answer 1

The following solution uses precomputed lookup tables for both forward and backward conversion.

// look up tables
var to_hex_array = [];
var to_byte_map = {};
for (var ord=0; ord<=0xff; ord++) {
    var s = ord.toString(16);
    if (s.length < 2) {
        s = "0" + s;
    }
    to_hex_array.push(s);
    to_byte_map[s] = ord;
}

// converter using lookups
function bufferToHex2(buffer) {
    var hex_array = [];
    //(new Uint8Array(buffer)).forEach((v) => { hex_array.push(to_hex_array[v]) });
    for (var i=0; i

This solution is faster than the winner of the previous benchmark: http://jsben.ch/owCk5 tested in both Chrome and Firefox on a Mac laptop. Also see the benchmark code for a test validation function.

[edit: I change the forEach to a for loop and now it's even faster.]