How can I get the source of an iframe?

Question

I have a mostly blank HTML page, that links to an iframe. The iframe page contains some text and 2 buttons tied to onclick scripts. I want to click the buttons, but I'm not able to get the values of getboundingclientrect when I supply the ID. How can I get the value of getboundingclientrect for an element (button) inside the iframe page in IE9?

Thanks for looking.

EDIT: made question more specific

Answer 1

Like this, if it is the same domain. If it is a different domain, it won't work.

var myIFrame = document.getElementById('iframename');
var content = myIFrame.contentWindow.document.body.innerHTML;

A different domain would be:

Parent: www.test.com
Child:  sub.test.com
or Child: www.testpage.com

It has to do with the same origin policy

Answer 2

As long as you're not doing something with a cross domain scenario this will work cross browser.

function getIFrameDoc(frame) {
   return frame.contentWindow ? frame.contentWindow.document : frame.contentDocument ? frame.contentDocument : frame.document;
}