The parent window is accessible via the
parent
window object, thus you can use the following javascript:
parent.document.getElementById('parentLabel').innerHTML='some other text!';
For a practicle example create the following two pages...
parent.htm:
<html>
<head>
<title>Parent Page</title>
</head>
<body>
<div id="parentLabel">this is some text.</div>
<iframe src="child.htm"></iframe>
</body>
</html>
and
child.htm:
<html>
<head>
<title>Child Page</title>
</head>
</head>
<body>
<a href="#" onclick="javascript:parent.document.getElementById('parentLabel').innerHTML='some other text!';return false;">update label</a>
</body>
</html>
Then open
parent.htm in your fav browser and click on the link in the framed page.