open popup window in asp.net

script language="javascript" type="text/javascript">

var win=null;

function NewWindow(mypage,myname,w,h,scroll,pos)
{
if(pos=="random"){LeftPosition=(screen.width)?Math .floor(Math.random()*(screen.width-w)):100;TopPosition=(screen.height)?Math.floor(Math.random()*((screen.height-h)-75)):100;}
if(pos=="center"){LeftPosition=(screen.width)?(screen.width-w)/2:100;TopPosition=(screen.height)?(screen.height-h)/2:100;}
else if((pos!="center" && pos!="random") || pos==null){LeftPosition=0;TopPosition=20}
settings='width='+w+',height='+h+',top='+TopPosition+',left='+LeftPosition+',scrollbars='+scroll+',l ocation=no,directories=no,status=no,menubar=no,too lbar=no,resizable=yes';
win=window.open(mypage,myname,settings);
}


/script>

input type="button" value="Add Course" onclick="NewWindow('RegisterCourse.aspx','Register','800','550','yes','center');return false" onfocus="this.blur()" />


from: http://p2p.wrox.com/asp-net-1-0-1-1-basics/36479-open-popup-window-asp-net.html