Control styling of elements within iFrame

im not sure if this is possible or not, but im trying to alter the style of elements contained within an iFrame using javascript.

I have tried the following which I believed in theory should work with no luck..开发者_高级运维.

<script>
function click() {
window.frames[0].document.getElementById('daLink').style.backgroundColor="#000";
}
</script>

<a href="#" onclick="click()" >Test</a>
<iframe src="http://www.google.co.uk" width="600" height="400" id="daLink"></iframe>

That will only work if the iFrame Source is on the same domain. Your code is not working due to the same-origin-policy!

Read more here: Javascript Security