title: how do i find if ul contains li with id in an if condition
body: <p>how do i find if ul contains li with id 'liSubTask1' exists or not in an if condition in jquery
  <code></p>
  
  <pre><code> &lt;ul id='ulTask'&gt;
     &lt;li id='liSubTask1'&gt;subTask1&lt;/li&gt;
     &lt;li id='liSubTask2'&gt;subTask2&lt;/li&gt;
     &lt;li id='liSubTask3'&gt;subTask3&lt;/li&gt;
     &lt;li id='liSubTask4'&gt;subTask4&lt;/li&gt;
     &lt;li id='liSubTask5'&gt;subTask5&lt;/li&gt;
   &lt;/ul&gt;
  </code></pre>
  
  <p></code></p>
  
  <p>i wanted to find out if "li with id" exists in ul then do some thing </p>