JS的全选

<th><input type="checkbox" name="checkAll"  id="checkAll" onclick="checkedAll()" />全选</th>


<td width="40"><input type="checkbox" id ="waybillNumber" name="waybillNumber" onclick="checkWaybillNumber()" value="" /></td>


    function  checkedAll(){
        if ($("#checkAll").prop("checked")) {
            $("input[type='checkbox'][name='waybillNumber']").prop("checked",true);
        } else {
            $("input[type='checkbox'][name='waybillNumber']").prop("checked",false);
        }
    }

    function   checkWaybillNumber(){
        if (!$("#waybillNumber").checked) {
            $("#checkAll").prop("checked", false);
        }
        var chsub = $("input[type='checkbox'][name='waybillNumber']").length;
        var checkedsub = $("input[type='checkbox'][name='waybillNumber']:checked").length;
        if (checkedsub == chsub) {
            $("#checkAll").prop("checked", true);
        }
    }