title: How to check input file is empty, and also display an alert if png format is selected using jquery
body: <p>I have got an input file upload , need to check which file is uploaded / if no file is selected by the client using jquery.</p>
  
  <pre><code>&lt;input type="file" name="files" id="file1" style="color:White" /&gt;
  &lt;input type="submit" value="Create" /&gt;
  </code></pre>
  
  <p>The check should trigger when submit is clicked.</p>