JS grid add delete save

<script type="text/javascript">
    var $ = function(id){
        return document.getElementById(id);
    }

    //全选
    function checkAll(target) {
        var checkeds = document.getElementsByName("b_id");
        for (var i = 0; i < checkeds.length; i++) {
            checkeds[i].checked = target.checked;
        }
    }

    //刷新行号
    function refreshRowNo() {
        var tbody = $("tbody");
        for (var i = 0; i < tbody.rows.length; i++) {
            tbody.rows[i].cells[0].innerHTML = i + 1;
        }
    }

    //添加行
    function AddRow() {
        var tbody = $("tbody");
        var row = tbody.insertRow(tbody.rows.length);
        row.insertCell(row.cells.length);
        row.insertCell(row.cells.length).innerHTML = '<input type="checkbox" name="b_id" />';
        row.insertCell(row.cells.length).innerHTML = '<input type="text" name="name" />';
        row.insertCell(row.cells.length).innerHTML = '<input type="text" name="number" />';
        row.insertCell(row.cells.length).innerHTML = '<input type="text" name="price" />';
        row.insertCell(row.cells.length).innerHTML = '<input type="text" name="sum" />';

        refreshRowNo();
    }

    //删除行
    function DelRow() {
        var checkeds = document.getElementsByName("b_id");
        var ischeck = false;
        for (var i = checkeds.length - 1; i >= 0; i--) {
            if (checkeds[i].checked) {
                ischeck = true;
                break;
            }
        }
        if (ischeck) {
            if (confirm("确定删除选中行?")) {
                for (var i = checkeds.length - 1; i >= 0; i--) {
                    if (checkeds[i].checked) {
                        var index = checkeds[i].parentNode.parentNode.rowIndex;
                        $("tbody").deleteRow(index - 1);
                    }
                }
                refreshRowNo();
            }
        } else {
            alert("请选中需要删除的行!");
        }
    }  

    //保存
    function Save() {
        var detail = [],
            tbody = $("tbody");
        for (var i = 0; i < tbody.rows.length; i++) {
            var name = tbody.rows[i].cells[2].childNodes[0].value;
            var number = tbody.rows[i].cells[3].childNodes[0].value;
            var price = tbody.rows[i].cells[4].childNodes[0].value;
            var sum = tbody.rows[i].cells[5].childNodes[0].value;
            var item = name + "^" + number + "^" + price + "^" + sum;
            detail.push(item);
        }
        var detailstr = detail.join("|");
        $("detail").value = detailstr;
        $("myform").submit();
    }

</script>

<form name="myform" action="AddOrder.aspx" method="post">
<input type="hidden" id="detail" name="detail" />
<ul>
    <li>采购单编号：<input type="text" id="CGDBH" name="CGDBH" /></li>
    <li>
        供应商名称：<input type="text" id="GYSMC" name="GYSMC" />
        <input type="button" onclick="AddRow()" value="增加一行" />
        <input type="button" onclick="DelRow()" value="删除" />
        <input type="button" onclick="Save()" value="保存" />
    </li>
</ul>
<table cellpadding="1" cellspacing="2">
    <tr>
        <th style="width:60px">序号</th>
        <th style="width:20px"><input type="checkbox" onclick="checkAll(this)" /></th>
        <th style="width:120px">名称</th>
        <th style="width:120px">数量</th>
        <th style="width:120px">单价</th>
        <th style="width:120px">总金额</th>
    </tr>
    <tbody id="tbody">
        <tr>
            <td>1</td>
            <td><input type="checkbox" name="b_id" /></td>
            <td><input type="text" name="name" /></td>
            <td><input type="text" name="number" /></td>
            <td><input type="text" name="price" /></td>
            <td><input type="text" name="sum" /></td>
        </tr>
    </tbody>
</table>
</form>