abstract：<!DOCTYPE html><html><head> <title></title> <style type="text/css"> .box{width: 100px;height: 280px;border: 1px solid #000;padding: 10px 6px;border-radiu
<!DOCTYPE html>
<html>
<head>
<title></title>
<style type="text/css">
.box{width: 100px;height: 280px;border: 1px solid #000;padding: 10px 6px;border-radius: 8px;}
#checked{margin: 8px auto;border-bottom: 1px solid;padding: 8px;}
.box input{margin: 8px;}
</style>
<script type="text/javascript">
function checkALL() {
var checkall,item;
checkall=document.getElementById('checkall')
item=document.getElementsByName('item[]')
for (var i = 0; i < item.length; i++) {
if (checkall.checked) {
item[i].checked=true;
}else{
item[i].checked=false;
}
}
}
</script>
</head>
<body>
<div class="box">
<div id="checked">
<input type="checkbox" id="checkall" onclick="checkALL()"><label for="checkall">全选</label>
</div>
<input type="checkbox" name="item[]">选项一<br>
<input type="checkbox" name="item[]">选项二<br>
<input type="checkbox" name="item[]">选项三<br>
<input type="checkbox" name="item[]">选项四<br>
<input type="checkbox" name="item[]">选项五<br>
<input type="checkbox" name="item[]">选项六<br>
<input type="checkbox" name="item[]">选项七<br>
</div>
</body>
</html>
Correcting teacher：天蓬老师Correction time：2019-06-04 13:23:57
Teacher's summary：全选的本质就是给每一个复选框添加一个checked
