實作效果：
html代碼：
1 <body>
2
3 <input type="checkbox" id="checkAll"/>全選<br>
4 <hr>
5 <input type="checkbox" name="color"/>紅色<br>
6 <input type="checkbox" name="color"/>黃色<br>
7 <input type="checkbox" name="color"/>藍色<br>
8
9 </body> JS代碼：
1 <script>
2 window.οnlοad=function()
3 {
4 document.getElementById("checkAll").onclick = checkall;
5 }
6 function checkall()
7 {
8 var dom = document.getElementById("checkAll");
9 var doms = document.getElementsByName("color");
10 for(var i = 0;i<doms.length;i++)
11 {
12 doms.item(i).checked = dom.checked;
13 }
14 }
15 </script> 轉載于:https://www.cnblogs.com/grnBlogs/p/4825649.html
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