title: How to click on a link and call function on the page that link go to as the same time?
body: <ul>
  <li>index.html - has menus <code>category1</code>, <code>category2</code>, <code>category3</code> </li>
  <li>product.html - has function <code>changeIframe([category1 | category2 | category3]);</code></li>
  </ul>
  
  <p>When I click a menu on "index.html" page, a link will bring me to "product.html" page then call function <code>changeIframe(var)</code> immediately. The <code>changeIframe(var)</code> function will compare <code>$var</code> (value of <code>var</code> is followed by the name of menu that I clicked) and then change content in this page. How can I do something like this?</p>