JSFiddle - React, Tailwind, and code Playground

by Adem GENC

HTML

<form action="" method="POST">
<input class = "new_input" type=text name="name[]" data-id="1"/>
<br />
<input class = "new_input" type=text name="name[]" data-id="2"/>
<br />
<input class = "new_input" type=text name="name[]" data-id="3"/>
<br />
<input class = "new_input" type=text name="name[]" data-id="4"/>
<br />
<input class = "new_input" type=text name="name[]" data-id="5"/>
<br />
<input class = "new_input" type=text name="name[]" data-id="6"/>
<br />
<input type="submit" value=" Validate " onclick="validate()" >
</form>

JavaScript

function validate() {
      var inputs = document.getElementsByTagName("input");
      var empty_inputs = 0;
      for(var i = 0; i < inputs.length; i++) {
          if(inputs[i].name.indexOf('name') == 0) { // check all inputs with 'name' in their name
              if (inputs[i].value == '') {
                  empty_inputs++;
                  alert($(inputs[i]).data("id"));
                  return false;
              }
          }
      }

  }