Reloading an IFrame via Ajax Request in Firefox and IE

Recently I was working on a web project where I needed to show a preview window which was basically an IFrame. As the whole page navigation was based on Ajax calls I was looking for a bulletproof method for reloading an IFrame.

The first solution (only Firefox)

IFrame code:

Ajax code:

var iframe = document.getElementById("preview_content");
iframe.contentDocument.location.reload(true);

Well, this solution was working quite nice with Firefox but IE wouldn’t reload the page at all.

The proper solution

Ajax code:

var iframe = document.getElementById("preview_content");
iframe.src = "preview.php?x="+Math.round(Math.random());

The additional parameter x (a random number) will cause IE to reload the IFrame properly without using the cache.