Javascript convert decimal to hexadecimal

Question

I need to convet from decimal to hexadecimal and keep the 0's

What I got i's

this.item = bytes[4].toString(16) + bytes[5].toString(16) + bytes[6].toString(16) + bytes[7].toString(16);

output:

79 2e 2 e1

i want:

79 2e 02 e1

Answer 1

So you want to pad leading 0s to every byte if it is below 10.

function toHex(bytes) {
  return bytes.reduce(function(string, byte) {
    return string + ("00" + byte.toString(16)).substr(-2);
  }, '');
}

Answer 2

This Function lets u change your decimal to any new base between 2 and 36.
For Example 255 and 16 would return FF

fromDecToBase:function(int, toNewBase) {
    var letters = ["0","1","2","3","4","5","6","7","8","9", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"];
    var returnValue= "";
    if (toNewBase > 1 && toNewBase < 37) {
        while(int != 0) {
            rest = int % toNewBase;
            int = Math.floor(int / toNewBase);
            returnValue= letters[rest] + returnValue;
        }
    }
    return returnValue;
},

All u need to do after it is check whether the string is 2 letters long or not which could be done the following way:

toHex:function(int) 
{
    hex = fromDecToBase(int, 16);
    return hex.length == 1 ? "0"+hex:hex;
},