<!DOCTYPE html> <html lang="en" xmlns:color="http://www.w3.org/1999/xhtml"> <head> <meta charset="UTF-8"> <title>登录</title> <nav class="navbar navbar-inverse" role="navigation"> <h2 align="center">首页</h2> <div>首页 <ul class="nav navbar-nav"> <script> function mySwitch() { var myele = document.getElementById("on_off") if (myele.src.match("bulbon")) { myele.src = "http://www.runoob.com/images/pic_bulboff.gif" document.getElementById("myBody").style.background = "white" document.getElementById("myBody").style.color = "black" } else { myele.src = "http://www.runoob.com/images/pic_bulbon.gif" document.getElementById("myBody").style.background = "black" document.getElementById(‘myBody‘).style.color = "white" } } </script> <body id="myBody"> <img id="on_off" onclick="mySwitch()" src="http://www.runoob.com/images/pic_bulbon.gif" width="50px"> </form> </body> </html> </head>
原文：http://www.cnblogs.com/caoxinwen092/p/7779503.html