关闭窗口 不弹出提示

<script language="javascript" type="text/javascript">
    function closeWindow() {
        var ua = navigator.userAgent
        var ie = navigator.appName == "Microsoft Internet Explorer" ? true : false
        if (ie) {
            var IEversion = parseFloat(ua.substring(ua.indexOf("MSIE ") + 5, ua.indexOf(";", ua.indexOf("MSIE "))))
            if (IEversion < 5.5) {
                var str = '<object id=noTipClose classid="clsid:ADB880A6-D8FF-11CF-9377-00AA003B7A11">'
                str += '<param name="Command" value="Close"></object>';
                document.body.insertAdjacentHTML("beforeEnd", str);
                document.all.noTipClose.Click();
            }
            else {
                parent.window.opener = null;
                parent.window.open('', '_self', ''); //for IE7
                parent.window.close();
            }
        }
        else {
            parent.window.close()
        }
    }
 </script>