Js实现动态更改Css样式之土豆网开/关灯效果!

1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

2 <html>

3 <head>

4 <title>开关灯效果</title>

5 <style type="text/css">

6 body

7 {

8 background: #FFF;

9 }

10 .day

11 {

12 background: #000;

13 }

14 .night

15 {

16 background: #FFF;

17 }

18 </style>

19 <script language="javascript" type="text/javascript">

20 function Switch() {

21 var btnSwitch = document.getElementById("btnSwitch");

22 var type = document.body.className;

23 if (type == "day") {

24 document.body.className = "night";

25 btnSwitch.value = "关灯";

26 } else {

27 document.body.className = "day";

28 btnSwitch.value = "开灯";

29 }

30 }

31 </script>

32 </head>

33 <body>

34 <input type="button" value="关灯" onclick="Switch()" />

35 </body>

36 </html>