这里介绍的JavaScript自动弹出窗口并自动关闭窗口，JS实现此特效似乎很简单，打开网页后即显示一个弹出窗口，之后会自动离开，使用了window.open和document.open();以及document.close();对象共同来实现，现在似乎用的不多了。
运行效果如下图所示：
具体代码如下：
<HTML> <HEAD> <TITLE>自动离开的窗口</TITLE> <SCRIPT> <!-- var flyingwin var popupwidth=200 var popupheight=150 var marginright var windowcenter var i_top=200 var i_left=-popupwidth-50 var step=40 var timer var waitingtime=5000 var pause=20 function showWindow() { flyingwin = window.open("", "flyingwin", "toolbar=no,width="+popupwidth+",height="+popupheight+",top=100,left="+(-popupwidth)+""); flyingwin.document.open(); flyingwin.document.write("<html><title>自动离开的窗口</title><body><p align=center>请不要关闭，马上就离开:(</body></html>"); flyingwin.document.close(); if (document.all) { marginright = screen.width+50 } if (document.layers) { marginright = screen.width+50 } windowcenter=Math.floor(marginright/2)-Math.floor(popupwidth/2) movewindow() } function movewindow() { if (i_left<=windowcenter) { flyingwin.moveTo(i_left,i_top) i_left+=step timer= setTimeout("movewindow()",pause) } else { clearTimeout(timer) timer= setTimeout("movewindow2()",waitingtime) } } function movewindow2() { if (i_left<=marginright) { flyingwin.moveTo(i_left,i_top) i_left+=step timer= setTimeout("movewindow2()",pause) } else { clearTimeout(timer) flyingwin.close() } } // --> </SCRIPT> </HEAD> <BODY onload=showWindow()> </BODY> </HTML>