[jQuery] 如何根据名字来选取checkbox数组 How to get the array of checkbox via name

<script type="text/javascript">
//<![CDATA[
jQuery(document).ready(function(){
    var j = jQuery("input[name='diagnostic[]']").length;
    jQuery("input[name='diagnostic[]']").each(function(e){
        if(jQuery(this).attr("checked") == false)
            j--;
    });
});
//Pay attention to the code marked with red color. After that, we can get that at least one checkbox is selected.
//]]>
</script>