string containing white space or not in react

if string contain white space alert should be unsuccessful and if string contain no white space alert should be successful
import React from “react”;
export default function DropDown() {

  let i=document.getElementById("input")?.value;
const submit=()=>{
  var whiteSpaceExp = /^s+$/g;
  if (whiteSpaceExp.test(i))
  {
  alert('unsuccess');
  }
  else
  {
    alert('success');
  }
  }
return (
    <>
      <form>
        <input type="text" id="input"  autoComplete="off" />
        <button onClick={submit}> click  </button>
      </form>
    </>
  );
}