GridView在编辑状态下每行某一列不出现编辑状态(该列在RowDataBound事件里有修改过)



这是前台代码

<asp:GridView ID="gv_fm" runat="server" CellPadding="10" ForeColor="#333333" 
            GridLines="None" onpageindexchanging="gv_fm_PageIndexChanging" 
             AllowPaging="True" PageSize="16" 
            AutoGenerateColumns="False" CellSpacing="1" DataKeyNames="FM_ID" 
            HorizontalAlign="Center" onrowdatabound="gv_fm_RowDataBound" 
            onrowediting="gv_fm_RowEditing" 
            onrowcancelingedit="gv_fm_RowCancelingEdit" onrowdeleting="gv_fm_RowDeleting" 
            onrowupdating="gv_fm_RowUpdating">
            <PagerSettings FirstPageText="首页" LastPageText="尾页" NextPageText="下一页" 
                        PreviousPageText="上一页" />
            <RowStyle BackColor="#EFF3FB" />
            <Columns>
                <asp:BoundField DataField="FM_ID" HeaderText="ID" />
                <asp:BoundField DataField="FM_Grade" HeaderText="机房模式">
                    <ItemStyle HorizontalAlign="Center" />
                    
                </asp:BoundField>
                <asp:BoundField DataField="FM_LogicID" HeaderText="逻辑码">
                    <ItemStyle HorizontalAlign="Center" />
                </asp:BoundField>
                <asp:BoundField DataField="FM_WorkingModel" HeaderText="工作模式">
                    <ItemStyle HorizontalAlign="Center" />
                </asp:BoundField>
                <asp:BoundField DataField="FM_FROutFreq" HeaderText="FM输出频率">
                    <ItemStyle HorizontalAlign="Center" />
       &