check window open

Question

var windowUrl = "";
var windowName = "mywin";
var w = window.open(windowUrl, windowName, windowSize);
w.document.write(html);
w.document.close();

This is tied to onclick. I do not want to write or close or even open if window exists (maybe refocus instead). I found some examples, but they do not seem to "work" (or do what I think I need.)

Answer 1

Try the following:

<script type="text/javascript">
function loadUniquePage(page) 
{
    if (opener && !opener.closed) {
        opener.focus();
    } else {
        var myWin = window.open(page,'','width=800,height=600');
        opener = myWin;
    }
}
</script>

also take a look at this question - JavaScript window.open only if the window does not already exist

also take a look on the link provided by @Aram Kocharyan:
https://developer.mozilla.org/en/DOM/window.closed