var Win;
function displayWindow(url, width, height,left,top) {
 if (Win){
 if (!Win.closed){
 Win.close();
 }
 }
 Win = window.open(url,"displayWindow",'width=' + width +',height=' + height + ',left=' + left + ',top=' + top + ',resizable=0,scrollbars=yes,menubar=no' );
}