Converts 4 byte Hex to 32 bit binary string

HexToBinary.js

function Hex32BitToBinary(HexData){
  let result = "";
  //32bit hex to string
  HexData.match(/.{1,2}/g).forEach(str => {
    result += hex2bin(str)
  });
  return result;
}

//Function to convert hex string to binary
function hex2bin(hex) {
  let regEx = /^[0-9]*$/g;
  let binary = ("00000000" + (parseInt(hex, 16)).toString(2)).substr(-8);
  if (regEx.test(binary)) {
    return binary;
  } else {
    return null;
  }
};