title: Client-side verification of HTML form
body: <p>I am using Django and Python to write a website. In one webpage, I have an HTML form, with a set of radio buttons and a submit button. On form submission, I want to verify that a radio button has in fact been selected, rather than all radio buttons left black as is default.</p>
  
  <p>One way of doing this is to do the check on the server side. I would check the POST data, and see whether the relevant field, indicating the selected radio button, has been set. If this field has not been set, then I would return to the same webpage, and display the message "Please try again". This works fine for me.</p>
  
  <p>However, this seems a bit of an overkill. Is there any way I can do this same check in Javascript (jQuery), and return this same webpage and error message?</p>