Closing child window when parent window closes in Jquery
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I have a window in which on a button click I open a window. Now I want the child window to close when my parent window is closed. I wrote unload function for the parent window but then the line of code which I try to access the child window throws an error.

My child window is opened using this script from code behind:

    "childWindow=window.open('MyPage.aspx,'ChildWindow','left=20, top=20, height=900, width=500,status= no, resizable= yes, scrollbars=yes, toolbar=no,location=no,menubar=yes'); childWindow.focus();"

In my parent unload function I am doing this:

    $(window).unload(function () {
    if ($(childWindow) != null)
        $(childWindow).close();});

I guess it is some problem with the way I access the child window. But I dont know the right way to access the child window which was created by a script from code behind.