Problem with getting the value on GridView

[doanthithanhnhan]

I'm working with GridView. But it seems rough.
When I add a Command Field (Edit, Update image button type) handly. The OnRowUpdating doesn't fire when I click on Update button.

Then I change by delete the Command Fiel I've created and use AutoGenerateEditButton property of the GridView and it does work. The function OnRowUpdating does fire.

But I've got another trouble with this way.
I can't get the changed value of the textbox in editting mode.

Here is my code:

<asp:GridView ID="grvDsMatHang" runat="server" 
                AutoGenerateColumns="true" AllowPaging="True" 
                PageSize="5" Width="98%" 
                OnRowCancelingEdit="grvDsMatHang_RowCancelingEdit" 
                OnRowEditing="grvDsMatHang_RowEditing" 
                OnRowUpdating="grvDsMatHang_RowUpdating"
                 AutoGenerateEditButton="true" 
 AutoGenerateDeleteButton="true" >

...<some definittions here>

<EditItemTemplate>
//my TextBox in editting mode
       <asp:TextBox ID="txtTenMH" runat="server" Text='' idth="50px"></asp:TextBox>
 
       <asp:HiddenField ID="hdnMoTa" runat="server" Value='<%# DataBinder.Eval(Container,"DataItem.MOTA") %>' />
 
</EditItemTemplate>

My code in .cs file to get the changed value of the TextBox

String n_Ten_MH = (row.FindControl("txtTenMH") as TextBox).Text;

The the value of n_Ten_MH still equals "" even I did type something in that textbox

Thanks in advance for noting my problems

[kenobewan]

Here is a quickstart article that may help:
Gridview

[Frinavale]

Are you doing a DataBind on your GridView in your PageLoad?
If you do a DataBind on your GridView before the Edit occurs, you will lose the data that was entered while editing.

-Frinny