title: Submit two forms with one click
body: <p>How do I submit two forms with only one click? There are two forms in my web page: one of them is displayed and has a submit button. And the other is hidden. Like the following:</p>
  
  <pre><code>&lt;form id="form1" action="/url1" method="post"&gt;
    ...
    &lt;input type="submit" value="Submit"&gt;
  &lt;/form&gt;
  
  &lt;!-- Hidden form --&gt;
  &lt;form id="form2" action="/url2" method="post"&gt;
    &lt;input type="hidden" ...&gt;
    &lt;input type="hidden" ...&gt;
    ...
  &lt;/form&gt;
  </code></pre>
  
  <p>How can I submit both of them by only clicking the button in the first form?</p>