在鼠标单击事件中编辑和更新网格视图行

我想在鼠标点击事件中编辑和更新网格视图行。如果用户单击某一行，则该行应变为可编辑，当他再次单击同一行时，该行应不可编辑，并且应保存更改。

我的网格视图看起来像：-

<asp:GridView ID="grdexcelsheet" runat="server" AllowPaging="True" 
                AutoGenerateColumns="False" RowStyle-HorizontalAlign="Left" HorizontalAlign="Center"
                onpageindexchanging="grdexcelsheet_PageIndexChanging" 
                Width = "100%" Height = "100%" Font-Size="Small">
                <PagerSettings Position="Bottom" Mode="NextPreviousFirstLast"  FirstPageText="First" 
                     LastPageText="Last"  NextPageText="Next" PreviousPageText="Prev" PageButtonCount="5" />
                <Columns>
                <asp:BoundField DataField="SrNo" HeaderText="SrNo" ReadOnly="true" />
                <asp:TemplateField HeaderText="CustomerFieldName">
                        <ItemTemplate>
                            <asp:Label ID="Label4" Runat="server" Text='<%# Bind("CustomerFieldName") %>'></asp:Label>
                        </ItemTemplate>
                        <EditItemTemplate>
                            <asp:TextBox ID="TextBox1" runat="server" Text='<%# Eval("CustomerFieldName") %>'>
                        </asp:TextBox>
                        </EditItemTemplate>
                     </asp:TemplateField>
                     <asp:BoundField DataField="CompanyFieldName" HeaderText="CompanyFieldName" ReadOnly="true" />
                     <asp:BoundField DataField="Usage" HeaderText="Usage" ReadOnly="true" />
                </Columns>
            </asp:GridView>