实现全选按钮的写法
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
.box{border: #CCCCCC solid ; height: 250px; width: 100px;margin: 0px auto;}
.box div{border-bottom:2px solid #CCCCCC;}
.box input{margin: 8px 2px;}
</style>
</head>
<body>
<script>
function Checkall(){
var checkall = document.getElementById('checkall');
var intem=document.getElementsByName('intem[]');
for(var i=0;i<intem.length;i++){
if(checkall.checked){
intem[i].checked = true;
}else{
intem[i].checked = false;
}
}
}
</script>
<div class="box">
<div>
<input type="checkbox" id="checkall" onclick="Checkall()"/>
<label for="checkall">全选</label>
</div>
<input type="checkbox" name="intem[]" />选项1<br />
<input type="checkbox" name="intem[]" />选项2<br />
<input type="checkbox" name="intem[]" />选项3<br />
<input type="checkbox" name="intem[]" />选项4<br />
<input type="checkbox" name="intem[]" />选项5<br />
</div>
</body>
</html>