Answers for "will js read a hexadecimal string"

javascript string to hex

var rgbToHex = function (rgb) { 
  var hex = Number(rgb).toString(16);
  if (hex.length < 2) {
       hex = "0" + hex;
  }
  return hex;
};

how to create hexadecimal encoded files in javascript

var bytes = Array(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15);
var ia = new Uint8Array(bytes);
var file = new File([ia], "hexfile.bin", {type: "application/octet-stream"});
document.location = URL.createObjectURL(file);
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