<script language=javascript> var m=5; //共几个Banner随机显示 var n=Math.floor(Math.random()*m+1) switch(n) { case 1: document.write('Banner1的HTML'); break; case 2: document.write('Banner2的HTML'); break; case 3: document.write('Banner3的HTML'); break; case 4: document.write('Banner4的HTML'); break; case 5: document.write('Banner5的HTML'); break; } </script>
如果一些如广告类的图片上需要加入相应的连接呢?那么代码仍然大同小异:
代码:
<SCRIPT LANGUAGE="javascript"> <!-- Begin var how_many_ads = 3; var now = new Date() var sec = now.getSeconds() var ad = sec % how_many_ads; ad +=1; if (ad==1) { txt="banner01"; url="http://siyizhu.com"; alt="banner01"; banner="http://siyizhu.com/images/banner/webbanner1.jpg"; width="778"; height="160"; } if (ad==2) { txt="banner02"; url="http://siyizhu.com"; alt="banner02"; banner="http://siyizhu.com/images/banner/webbanner2.jpg"; width="778"; height="160"; } if (ad==3) { txt="banner03"; url="http://siyizhu.com"; alt="banner03"; banner="http://siyizhu.com/images/banner/webbanner3.jpg"; width="778"; height="160"; } document.write('<center>'); document.write('<a href="' + url + '" target="_top">'); document.write('<img src="' + banner + '" width=') document.write(width + ' height=' + height + ' '); document.write('alt="' + alt + '" border=0><br>'); document.write('<small>' + txt + '</small></a>'); document.write('</center>'); // End --> </SCRIPT>