查询出相关信息后，勾选第二跳信息，然后点击报废按钮，将编号为04-0001的一体机在数据表tb_equipment中的isactive列的值从1变为0（就是使用状态改为报废的意思）
前台代码：
<asp:GridView ID=”GridView1″ runat=”server” AllowPaging=”True” 
                    AllowSorting=”True” AutoGenerateColumns=”False” BorderColor=”#000066″ 
                    CellPadding=”4″ ForeColor=”#333333″ GridLines=”Vertical” PageSize=”5″ 
                    DataKeyNames=”number” EnableViewState=”False” >
                    <RowStyle BackColor=”#F7F6F3″ ForeColor=”#333333″ />
                    <Columns>
                        <asp:TemplateField HeaderText=”选择”>
                         <ItemTemplate>
                         <asp:CheckBox id=”cbxId” runat=”Server” />
                         </ItemTemplate>
                        </asp:TemplateField>
                        <asp:BoundField DataField=”number” HeaderText=”自编码” />
                        <asp:BoundField DataField=”name” HeaderText=”设备名称” />
                        <asp:BoundField DataField=”kind” HeaderText=”品牌” />
                        <asp:BoundField DataField=”peizhi” HeaderText=”配置” />
                        <asp:BoundField DataField=”company” HeaderText=”单位” />
                        <asp:BoundField DataField=”department” HeaderText=”部门” />
                        <asp:BoundField DataField=”round” HeaderText=”线路” />
                        <asp:BoundField DataField=”useplace” HeaderText=”使用地点” />
                        <asp:BoundField DataField=”usetime” HeaderText=”使用日期” />
                        <asp:HyperLinkField HeaderText=”分配” 
                            Text=”调整” DataNavigateUrlFields=”number” 
                            DataNavigateUrlFormatString=”~/设备领用/调整/change.aspx?number={0}” />
                    </Columns>
                    <FooterStyle BackColor=”#5D7B9D” Font-Bold=”True” ForeColor=”White” />
                    <PagerStyle BackColor=”#284775″ ForeColor=”White” HorizontalAlign=”Center” />
                    <SelectedRowStyle BackColor=”#E2DED6″ Font-Bold=”True” ForeColor=”#333333″ />
                    <HeaderStyle BackColor=”#5D7B9D” Font-Bold=”True” ForeColor=”White” />
                    <EditRowStyle BackColor=”#999999″ />
                    <AlternatingRowStyle BackColor=”White” ForeColor=”#284775″ />
                </asp:GridView>
CS代码：
protected void Button4_Click(object sender, EventArgs e)
    {
        string[] n =new string[5];
        string pl;
        for (int i = 0; i < GridView1.Rows.Count; i++)
        {
            CheckBox cbx = (CheckBox)GridView1.Rows[i].FindControl(“cbxId”);
            if (cbx.Checked == true)
            {
                pl = GridView1.DataKeys[i].Value.ToString();
                string sqlText = “update tb_equipment set isactive = 0 where isactive=1 and number=”””+pl+””””;
                z.ExecSql(sqlText);
            }
        }
    }
我的本意是点击”报废“按钮，循环遍历GridView1控件中的所有行，找出其中 CheckBox勾选的行信息，每一行的自编码，对应数据表中的number字段，是唯一确定各个设备的。isactive为1表示设备可以使用，为0则表示报废。请大家看下代码该怎么写