Check all input values of same class is empty jquery

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input type="text" class="MyClass" />
<input type="text" class="MyClass" />
<input type="text" class="MyClass" />
<button>test</button>

$('button').click(function() {
  var $nonempty = $('.MyClass').filter(function() {
    return this.value != ''
  });

  if ($nonempty.length == 0) {
    alert('empty')
  }
})

Or using a flag

$('button').click(function() {
  var flag = false;
  $('.MyClass').filter(function() {
    if (this.value != '') {
      flag = true;
      //no need to iterate further
      return false;
    }
  });

  if (!flag) {
    alert('empty')
  }
})