全选，全不选
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style>
.box{
width: 200px;
height: 150px;
border: 1px solid #000;
padding-bottom: 8px;
margin: 10px auto;
}
.box div{
border-bottom: 1px solid #ccc;
margin-bottom: 5px;
}
</style>
</head>
<body>
<div class="box">
<div>
<label ><input id="aa" type="checkbox" /> 全选</label>
</div>
<input type="checkbox" name="item" />选项1<br />
<input type="checkbox" name="item" />选项2<br />
<input type="checkbox" name="item" />选项3<br />
<input type="checkbox" name="item" />选项4<br />
<input type="checkbox" name="item" />选项5<br />
<input type="checkbox" name="item" />选项6<br />
</div>
<script>
var lable=document.getElementById('aa');
var items=document.getElementsByName('item');
lable.onclick=function(){
for(var i=0;i<items.length;i++){
if(aa.checked)
{
items[i].checked=true
}
else{
items[i].checked=false
}
}
}
</script>
</body>
</html>