比较简单、好理解的写法，做个备注。查看请前往原地址：http://blog.csdn.net/graceup/article/details/46650781
<html>
<body>
<table border="1">
<tr>
<th><input type="checkbox" onclick="swapCheck()" /></th>
<th>Month</th>
<th>Savings</th>
</tr>
<tr>
<td><input type="checkbox" /></td>
<td>January</td>
<td>$100</td>
</tr>
<tr>
<td><input type="checkbox" /></td>
<td>February</td>
<td>$150</td>
</tr>
</table>
<script type="text/javascript"
src="http://apps.bdimg.com/libs/jquery/2.1.1/jquery.min.js"></script>
<script type="text/javascript">
//checkbox 全选/取消全选
var isCheckAll = false;
function swapCheck() {
if (isCheckAll) {
$("input[type='checkbox']").each(function() {
this.checked = false;
});
isCheckAll = false;
} else {
$("input[type='checkbox']").each(function() {
this.checked = true;
});
isCheckAll = true;
}
}
</script>
</body>
</html>