how to convert an r, g, and b to a hex code in js code example

Example: javascript rgb to hex

function rgbToHex(r, g, b) {
  return "#" + ((1 << 24) + (r << 16) + (g << 8) + b).toString(16).slice(1);
}

function hexToRgb(hex) {
  var result = /^#?([a-fd]{2})([a-fd]{2})([a-fd]{2})$/i.exec(hex);
  if(result){
      var r= parseInt(result[1], 16);
      var g= parseInt(result[2], 16);
      var b= parseInt(result[3], 16);
      return r+","+g+","+b;//return 23,14,45 -> reformat if needed 
  } 
  return null;
}
console.log(rgbToHex(10, 54, 120)); //#0a3678
console.log(hexToRgb("#0a3678"));//"10,54,120"