1 <!doctype html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Document</title> 6 <style> 7 ul 8 { 9 list-style: none; 10 11 } 12 #aa 13 { 14 width: 200px; 15 height: 100px; 16 background: pink; 17 } 18 ul #a 19 { 20 width: 200px; 21 height: 500px; 22 background: #3c3c3c; 23 } 24 </style> 25 </head> 26 <body> 27 <ul> 28 <li id="aa"></li> 29 <li id="a"></li> 30 </ul> 31 32 33 <script> 34 var chan1=document.getElementById(‘aa‘); 35 var chan2=document.getElementById(‘a‘); 36 chan1.onclick=function (){ 37 if (chan2.style.display=="block") { 38 chan2.style.display="none"; 39 }else{ 40 chan2.style.display="block"; 41 }; 42 }; 43 44 </script> 45 </body> 46 </html>
原文：http://www.cnblogs.com/yoyoyoyoyoyo/p/5815500.html