GridView行更新和DropList

Question

I have a gridview with column that have droplist when enter edit mode:

<asp:TemplateField HeaderText="genre" SortExpression="genre">
                    <EditItemTemplate>
                        <asp:DropDownList ID="DropDownList2" runat="server" 
                            DataSourceID="SqlDataSource1" DataTextField="name" DataValueField="name">
                        </asp:DropDownList>
                    </EditItemTemplate>
                    <ItemTemplate>
                        <asp:Label ID="Label1" runat="server" Text='<%# Bind("genre") %>'></asp:Label>
                    </ItemTemplate>
                </asp:TemplateField>

Now i want to take it to UpdateParameters of SqlDataSource :

    <UpdateParameters>
            <asp:ControlParameter ControlID="DropDownList2" Type="string" PropertyName="SelectedValue" Name="genre" />
    </UpdateParameters>

But when i pressed he give me Error msg

Could not find control 'DropDownList2' in ControlParameter 'genre'. 

Any idea why?

Answer 1

DropDownList2 is a nested control located under the Grid; therefore, your SqlDataSource control does not have visibility at all of the DropDownList2.

You could try assigning the value on the code behind by using the Updating event:

protected void SqlDataSource_Updating(object sender, SqlDataSourceCommandEventArgs e)
{
  e.Command.Parameters["@genre"].Value = GetDropDownListValue();
}

Note: You will need to use FindControl("DropDownList2") in GetDropDownListValue()