How to access parent Iframe from JavaScript

Well, I have an IFrame, which calls a same domain page. My problem is that I want to access some information from this parent Iframe from this called page (from JavaScript). How can I access this Iframe?

Details: There are several Iframes just like this one, that can have the same page loaded, because I am programming a Windows environment. I intend to close this Iframe, that's why I need to know which I should close from inside him. I have an array keeping references to these Iframes.

EDIT: There iframes are generated dynamically

Also you can set name and ID to equal values

<iframe id="frame1" name="frame1" src="any.html"></iframe>

so you will be able to use next code inside child page

parent.document.getElementById(window.name);

Simply call window.frameElement from your framed page. If the page is not in a frame then frameElement will be null.

The other way (getting the window element inside a frame is less trivial) but for sake of completeness:

/**
 * @param f, iframe or frame element
 * @return Window object inside the given frame
 * @effect will append f to document.body if f not yet part of the DOM
 * @see Window.frameElement
 * @usage myFrame.document = getFramedWindow(myFrame).document;
 */
function getFramedWindow(f)
{
    if(f.parentNode == null)
        f = document.body.appendChild(f);
    var w = (f.contentWindow || f.contentDocument);
    if(w && w.nodeType && w.nodeType==9)
        w = (w.defaultView || w.parentWindow);
    return w;
}