Converting hexadecimal to float in JavaScript

Question

I would like to convert a number in base 10 with fraction to a number in base 16.

var myno = 28.5;

var convno = myno.toString(16);
alert(convno);


        

Answer 1

Here is a size-improvement of Mark Eirich's answer:

function hex2dec(hex) {
  let h = hex.split(/\./);
  return ('0x'+h[1])*(16**-h[1].length)+ +('0x'+h[0]);
}

function hex2dec(hex) {
  let h = hex.split(/\./);
  return ('0x'+h[1])*(16**-h[1].length)+ +('0x'+h[0]);
}

function calc(hex) {
  let dec = hex2dec(hex);
  msg.innerHTML = `dec: <b>${dec}</b><br>hex test: <b>${dec.toString(16)}</b>`
} 

let init = "bad.a55";
inp.value = init;
calc(init);

<input oninput="calc(this.value)" id="inp" /><div id="msg"></div>