Syntax
window.frames["frameName"]
window.frames[num]
The frames property contains an array that stores each frame instance created with the tag, in a document.
Array entries can be referenced either by index number or by the name assigned by the NAME attribute of the tag.
<html>
<script language="JavaScript">
<!--
for(var i = 0; i <= window.frames.length; i++){
newWin.document.write("The name of frame #" + i);
newWin.document.write(" is " + window.frames[i].name + "<br>");
}
-->
</script>
</html>