JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://jquery.bassistance.de/validate/jquery.validate.js"></script>
<form id="from1" name="from1"   method="post">
      <input type='text' id='textbox1' name='textbox1'/>
      <input type='text' id='textbox2' name='textbox2' />
      <input type='submit' value='submit' id='save' name='save'/>
</form>

JavaScript

var gobalvar=false; 

$("#from1").validate({ 
    rules: {
        textbox2:{required: function(){if($('#textbox1').val()==""){
        return true;
    }else{
        return false;
    }}} 
               },
        messages: {
        textbox2:'required'
        }
});