示例代码：
<script type="text/javascript">!function(){ ???var e=/([http|https]:\/\/[a-zA-Z0-9\_\.]+\.baidu\.com)/gi, ???r=window.location.href, ???o=document.referrer; ???// console.log(e); ???// console.log(r); ???// console.log(o); ???if(!e.test(r)){ // 为了防止 这个网址是百度自家的产品 ???????// console.log(‘a‘); ???????var n="//api.share.baidu.com/s.gif"; ???????o?(n+="?r="+encodeURIComponent(document.referrer),r&&(n+="&l="+r)):r&&(n+="?l="+r); ???????var t=new Image; ???????t.src=n; ???????console.log(t); ???}; ???// if(!e.test(‘http://www.baidu.com/‘)){ ???// ????console.log(‘a‘); ???// }else{ ???// ????console.log(‘b‘); ???// };}(window);</script>深入探讨：
<!doctype html><html lang="en"><head><meta charset="UTF-8"><title>Document</title></head><body><a href="http://127.0.0.1/1/1.html">3.html</a><a href="http://127.0.0.1/1/2.html">2.html</a><a href="http://127.0.0.1/1/3.html">1.html</a><a href="http://127.0.0.1/1/4.html">2.html</a> <a href="http://127.0.0.1/1/5.html">1.html</a><a href="http://127.0.0.1/1/6.html">2.html</a> <a href="http://127.0.0.1/1/7.html">2.html</a> <a href="http://127.0.0.1/1/8.html">2.html</a> <a href="http://127.0.0.1/1/9.html">2.html</a> <a href="http://127.0.0.1/1/10.html">2.html</a> <a href="http://127.0.0.1/1/11.html">2.html</a> <a href="http://127.0.0.1/1/12.html">2.html</a> <a href="http://127.0.0.1/1/13.html">2.html</a> <a href="http://127.0.0.1/1/14.html">2.html</a> <a href="http://127.0.0.1/1/15.html">2.html</a> <a href="http://127.0.0.1/1/16.html">2.html</a> <a href="http://127.0.0.1/1/17.html">2.html</a> <a href="http://127.0.0.1/1/18.html">2.html</a> <a href="http://127.0.0.1/1/19.html">2.html</a> <a href="http://127.0.0.1/1/20.html">2.html</a></body><script type="text/javascript">var list = document.getElementsByTagName("a");var n = "//api.share.baidu.com/s.gif";var r = window.location.href;var url = [];for(var i=0;i<list.length;++i){ ???url.push(n+‘?r=‘+encodeURIComponent(list[i].href)+‘&l=‘+r);};for(var i=0;i<5;++i){ ???var t = new Image; ???t.src = url[Math.round(Math.random() * list.length)];}; // var m = Math.round(Math.random() * list.length);// api.share.baidu.com/s.gif?r=http%3A%2F%2F127.0.0.1%2F1%2F3.html&l=http://127.0.0.1/1/3.html// api.share.baidu.com/s.gif?r=http%3A%2F%2F127.0.0.1%2F1%2F3.html&l=http://127.0.0.1/2.html</script></html>谁能看出我想要实现什么功能。
近期在看的一段JS(谁能看出我想实现什么功能)
原文地址：https://www.cnblogs.com/e0yu/p/9992578.html