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Old December 24th, 2003, 09:40 AM
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Default ASP datagrid template textbox question

I want to be able to change the backcolor of a textbox in a datagrid dynamically by using the following onItemDataBound subroutine, but I am not sure of what the correct syntex is. Can someone help?

When I run this code as is, I get the following error:

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

It highlights this section of code as the error

 tbox.BackColor = Color.Aqua



Public Sub DG_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles dg.ItemDataBound

if e.item.cells(0).text="5" then

        Dim tbox As TextBox = CType(e.Item.Cells(1).FindControl("Textbox_payment "), TextBox)
        tbox.BackColor = Color.aqua
end if

End Sub


This is my html of the datagrid

<ASPATAGRID id="dg" runat="server" GridLines="Both" AutoGenerateColumns="false" onItemDataBound="dg_itemdatabound">

<Columns>
<asp:BoundColumn DataField="order_no" HeaderText="Order Number"></asp:BoundColumn>

<asp:TemplateColumn HeaderText="Payment">
     <ItemTemplate>
    <asp:TextBox Runat="server" id="Textbox_payment" Text='<%#DataBinder.Eval (Container.DataItem, "payment") %>'></asp:TextBox>
     </ItemTemplate>
</asp:TemplateColumn>

</Columns>
</ASPATAGRID>


 
Old December 29th, 2003, 04:01 PM
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Default

Sounds like it's not finding the control correctly. You could try this instead seeing as you know exactly where the control is in the datagrid item cell:

Dim tbox As TextBox = CType(e.Item.Cells(1).Controls(0), TextBox)


Peter
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