JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="userinput" name="userinput"/>
<button onclick="inputhandler()">TEST</button>

<script>
function inputhandler() {
  var text = document.getElementById('userinput').value;
  alert(text);
  
  /*DRAGONS BE HERE*/
  /*THEN*/
  /*USE AJAX HERE TO PASS THE RESULTS TO PHP SCRIPT*/
}
</script>