jquery判断checkbox最多选几个?

<!DOCTYPE html>

<html >

<head>

<meta charset="UTF-8">

<title></title>

<script src="js/jquery.min.js"></script>

</head>

<body>

<div class="checkbox">

<input type="checkbox"/>

</div>

<div class="checkbox">

<input type="checkbox"/>

</div>

<div class="checkbox">

<input type="checkbox"/>

</div>

<div class="checkbox">

<input type="checkbox"/>

</div>

<div class="checkbox">

<input type="checkbox"/>

</div>

<div class="checkbox">

<input type="checkbox"/>

</div>

<script type="text/javascript">

$(function(){

$('.checkbox').find('input').click(function(){

if($("input[type=checkbox]:checked").length >= 6)

{

$(this).removeAttr("checked");

alert("最多选5个!")}

});

})

</script>