title: How to check if dropdown has one value or none in jquery?
body: <p>What I want to do is check if a drop down has one value or none and then make it read only?</p>
  
  <pre><code>if(){
   $('#dropdown').attr("disabled", "disabled");
  }
  
  
  &lt;select class="dropdown" name="dropdown" id="dropdown"&gt;
          &lt;option value="L6.5"&gt;L6.5&lt;/option&gt;
     &lt;/select&gt; 
  
  &lt;select class="dropdown" name="dropdown2" id="dropdown2"&gt;&lt;/select&gt;
  
  
  &lt;select class="dropinput" name="dropdown3" id="dropdown3"&gt;
         &lt;option value=""&gt;&lt;/option&gt;
         &lt;option value=""&gt;&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>I need all top three dropdowns to be disabled</p>