使用JQuery获取选中的Checkbox：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.min.js"></script>
</head>
<body>
<input type="checkbox" name="test" value="1" checked/>
<input type="checkbox" name="test" value="2" checked/>
</body>
<script type="text/javascript">
//选中状态数组的长度
console.log($(":checked").length);
$(":checked").each(function (index, value) {
//index是循环下标,从0开始
console.log(index + ":" + $(this).val());
});
</script>
</html>