or
function UseMainRadWindow() {
var width = screen.width;
var height = screen.height;
var mapPosition = '<%= Session["MapPositionSession"].ToString() %>'
var ctgrsLst = document.getElementById('ResultsLabel').innerText;
var oWnd = $find("<%= RadWindow1.ClientID %>");
oWnd.show();
oWnd.setUrl("Pages/FullMaps/MainMap.aspx?width=" + width.toString() + "&height=" + height.toString() + "&mapPosition=" + mapPosition.toString() + "&ctgrsLst=" + ctgrsLst.toString().replace(" & ", "."));
oWnd.maximize();
}