title: Check if element doesn't have attribute jQuery
body: <p><code>onClick</code> of an item it adds an attribute. Only three items can be selected so they'll only ever be three elements on the page with the attribute like : <code>data-selected: 1</code>, <code>data-selected: 2</code> or <code>data-selected: 3</code>.</p>
  
  <pre><code>if ($('.item').attr('data-selected', '1') || $('.item').attr('data-selected', '1') || 
      $('.item').attr('data-selected', '1')) {
  }
  </code></pre>
  
  <p>I can do an if statement to check if an element has an <code>attribute</code>, how do I check if all the elements with <code>.item</code> class have an attribute and if not then do something.</p>