原始
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>jQuery实现CheckBox全选、全不选</title>
<script src="http://code.jquery.com/jquery-1.4.4.min.js" type="text/javascript"></script> <script type="text/javascript">
$(function() {
$("#checkAll").click(function() {
$('input[name="subBox"]').attr("checked",this.checked);
});
var $subBox = $("input[name='subBox']");
$subBox.click(function(){
$("#checkAll").attr("checked",$subBox.length == $("input[name='subBox']:checked").length ? true : false);
});
});
</script>
</head>
<body>
<div>
<input id="checkAll" type="checkbox" />全选
<input name="subBox" type="checkbox" />项1
<input name="subBox" type="checkbox" />项2
<input name="subBox" type="checkbox" />项3
<input name="subBox" type="checkbox" />项4
</div>
</body>
改进
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<div><input name="checkbox-all" type="checkbox"/>全选</div>
<ul>
<li><input name="checkbox-item" type="checkbox"/>1</li>
<li><input name="checkbox-item" type="checkbox"/>2</li>
<li><input name="checkbox-item" type="checkbox"/>3</li>
<li><input name="checkbox-item" type="checkbox"/>4</li>
</ul>
</body>
</html>
<script src="http://code.jquery.com/jquery-1.4.4.min.js" type="text/javascript"></script>
<script>
$(function(){
var checkboxAll = $("input[name='checkbox-all']");
var checkboxItem = $("input[name='checkbox-item']");
checkboxAll.change(function(){
checkboxItem.attr("checked",this.checked)
})
checkboxItem.change(function(){
//只能在里面声明，因为change，才会变化
var checkboxItemChecked = $("input[name='checkbox-item']:checked").length;
if(checkboxItem.length == checkboxItemChecked){
checkboxAll.attr("checked",true)
}else{
checkboxAll.attr("checked",false)
}
})
})
</script>
