title: jquery if none selected from drop down
body: <p>i had this code:</p>
  
  <pre><code>    $("#source_lang, #targ_lang").each(function(index, element) {
  
          if ($(this +'option:selected').length== 0) {
          //some code 
          }
          }
  </code></pre>
  
  <p>I want to display error messages when none of items on the lists is selected. 
  This gives me no results(the error message doesn't show). </p>