JavaScript bufToHex, hexToBuf, hexToString, stringToHex

// JavaScript bufToHex, hexToBuf, hexToString, stringToHex

 

// JavaScript bufToHex, hexToBuf, hexToString, stringToHex

function bufToHex (buffer) { // buffer is an ArrayBuffer
    return Array.prototype.map.call(new Uint8Array(buffer), x => ('00' + x.toString(16)).slice(-2)).join('');
}

function hexToBuf (hex) {
    var typedArray = new Uint8Array(hex.match(/[\da-f]{2}/gi).map(function (h) {
        return parseInt(h, 16)
    }));
    
    return typedArray.buffer;
}

function hexToString (hex) {
    var arr = hex.split("");
    var out = "";
    
    for (var i = 0; i < arr.length / 2; i++) {
      var tmp = "0x" + arr[i * 2] + arr[i * 2 + 1];
      var charValue = String.fromCharCode(tmp);
      out += charValue;
    }
    
    return out;
}

function stringToHex (str) {
    var val = "";
    
    for (var i = 0; i < str.length; i++) {
      if (val == "")
        val = str.charCodeAt(i).toString(16);
      else
        val += str.charCodeAt(i).toString(16);
    }
    val += "0a";
    
    return val;
}

var test = "abc";
var hex = stringToHex(test);
console.log(hex);

var str = hexToString(hex);
console.log(str);


var buf = hexToBuf(hex);
console.log(buf);
console.log(Buffer.from("abc"));

var hex2 = bufToHex(buf);
console.log(hex2);

//result: 

6162630a
abc
ArrayBuffer { [Uint8Contents]: <61 62 63 0a>, byteLength: 4 }

6162630a