设置打开网页的一些属性

function login(){
    var mode='status=no,resizable=no,scrollbars=no,'
    var size1='left='+screen.width*2/7+',top='+screen.height*2/5+',width='+screen.width*2/5+',height='+screen.height*2/7;
    var size2='left='+screen.width/5+',top='+screen.height/5+',width='+screen.width*3/5+',height='+screen.height*2/5;
    var urlstr="login.aspx";
    if (screen.width>640)
      window.open(urlstr,'login',mode+size1);
    else
      window.open(urlstr,'login',mode+size2);
}