il problema è che non prende il valore dalla boundcolumn:

dim val as string=replace(ctype(e.item.cells(0).controls(0), textbox).text,"'","''")

questa è tutta la pagina se può servire


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<%@ Page Language="vb" Debug="true" %>
<%@ import namespace="system.data" %>
<%@ import namespace="system.data.oledb" %>

<script language="VB" runat="server">

dim objconn as new oledbconnection ("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & server.MapPath("scuola_dansalsa2.mdb"))


sub page_load (obj as object, e as eventargs)
dim objcmd as new oledbdataadapter ("select * from mesi", objconn)

dim ds as dataset=new dataset()
objcmd.fill (ds,"mesi")

mydatagrid.datasource=ds.tables("mesi").defaultvie w
mydatagrid.databind

end sub

sub modifica (obj as object, e as datagridcommandeventargs)

mydatagrid.edititemindex=e.item.itemindex

dim objcmd as new oledbdataadapter ("select * from mesi", objconn)

dim ds as dataset=new dataset()
objcmd.fill (ds,"mesi")

mydatagrid.datasource=ds.tables("mesi").defaultvie w
mydatagrid.databind
end sub



sub modifica_mesi (obj as object, e as datagridcommandeventargs)

dim val as string=replace(ctype(e.item.cells(0).controls(0), textbox).text,"'","''")
dim sql_val as string=" update mesi set mesi='"& val &"' where id=" & mydatagrid.datakeys(e.item.itemindex)
funzione(sql_val)


dim objcmd as new oledbdataadapter ("select * from mesi", objconn)

dim ds as dataset=new dataset()
objcmd.fill (ds,"mesi")

mydatagrid.datasource=ds.tables("mesi").defaultvie w
mydatagrid.databind

end sub
function funzione(sql_val)
dim objcmd as new oledbcommand (sql_val, objconn)
objcmd.connection.open()
objcmd.executenonquery()
objcmd.connection.close()
end function





</script>



<form runat="server">

<asp:datagrid OnEditCommand="modifica" OnUpdateCommand="modifica_mesi" AutoGenerateColumns="false" id="mydatagrid" runat="server" DataKeyField="id">

<columns>

<asp:boundcolumn HeaderText="mesi" DataField="mesi" HeaderStyle-Width="50"/>

<asp:buttoncolumn HeaderText="" Text="elimina" CommandName="delete"/>
<asp:editcommandcolumn EditText="modifica" CancelText="deseleziona" UpdateText="modifica dato" ItemStyle-Wrap="false" HeaderText="modifica dati allievo" />
</columns>
</asp:datagrid>







</form>