JSFiddle - React, Tailwind, and code Playground

by olegatilla

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<textarea name="txtarea">sdfsdf</textarea>
<button  id ="btn">Button</button>

JavaScript

//Initially hide button
$('#btn').hide();

//Textarea keyup function
$('textarea[name=txtarea]').keyup(function(){
  if($.trim($(this).val()).length  <= 0)$('#btn').hide()
  else $('#btn').show()
});