javascript 全选
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>全选</title>
<style>
.box{
width:120px;
height:250px;
border:1px solid #000;
border-radius: 5px;
padding: 5px 10px;
margin:20px auto;
}
.box div{
border-bottom: 1px solid #000;
padding-bottom: 10px;
margin-bottom: 8px;
}
.box input{
margin: 8px;
}
</style>
<script>
function checkAll() {
var checkall,item;
checkall = document.getElementById("checkall");//获取全选
item = document.getElementsByName("item[]");//获取下面的勾选框
for (var i =0 ;i<item.length;i++){
if(checkall.checked){
item[i].checked = true; //当全选被选中时，下面的勾选框选中
}else{
item[i].checked = false;//反之
}
}
}
</script>
</head>
<body>
<div class="box">
<div>
<input type="checkbox" id ="checkall" onclick="checkAll();"><label for="checkall">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>
</body>
</html>
<!-- 疑问，怎么调整，让下面的全部选中时上面的全选也选中？ -->