"I use javascript to open a new window

window.open(URL,Name,""width=400, height=400"");

How to put the window in the middle of screen?(If I use top,left by pixel,

the window is not in center if screen mode changes)

Can anyone help?Thanx in advance.
"

"<s-cript type=""text/j-avascript"">
function NewWindow(mypage,myname,w,h)
{
LeftPosition = (screen.width) ? (screen.width-w)/2 : 0;
TopPosition = (screen.height) ? (screen.height-h)/2 : 0;
settings

='height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+','
win = window.open(mypage,myname,settings)
if(win.window.focus){win.window.focus();}
}
</script>

<button on-click=""NewWindow('www.google.com/','Name',400,400);"">New

Centered Window</button>"