<!DOCTYPE html> <html> <head> <title>MyHtml.html</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <script type="text/javascript"> window.onload = function() { var flag=false; document.getElementById("all").onclick=function(){ flag=!flag; var items=document.getElementsByName("item"); for(var x=0;x<items.length;x++){ items[x].checked=flag; } }; document.getElementById("unall").onclick=function(){ var items=document.getElementsByName("item"); for(var x=0;x<items.length;x++){ items[x].checked=!items[x].checked; } }; } </script> </head> <body> <div>商品列表</div> <input type="checkbox" name="item" value="3000" />笔记本3000元<br /> <input type="checkbox" name="item" value="2500" />HTC手机2500<br /> <input type="checkbox" name="item" value="8000" />苹果电脑8000<br /> <input type="checkbox" name="item" value="1500" />IPAD1500<br /> <input type="checkbox" name="item" value="400" />玩具汽车400<br /> <input type="button" value="总金额" onclick="getSum()" /> <input type="button" value="全选/全不选" id="all" /> <input type="button" value="反选" id="unall" /> <span id="sumId"></span> </body> </html>
原文：http://www.cnblogs.com/spadd/p/4192608.html