Question

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"  Onrowupdating="GridView1_RowUpdating" onrowediting="GridView1_RowEditing">
    <Columns>
        <asp:TemplateField HeaderText="Test">
            <EditItemTemplate>
                <asp:UpdatePanel ID="up1" runat="server" UpdateMode="Conditional">
                    <ContentTemplate>
                        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" 
                            OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
                            <asp:ListItem>Test1</asp:ListItem>
                            <asp:ListItem>Test2</asp:ListItem>
                            <asp:ListItem>Test3</asp:ListItem>
                        </asp:DropDownList>
                    </ContentTemplate>
                </asp:UpdatePanel>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label1" runat="server" Text='<%# Bind("SS") %>' />
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Rate">
            <EditItemTemplate>
                <asp:UpdatePanel ID="up2" runat="server" UpdateMode="Conditional">
                    <ContentTemplate>
                        <asp:DropDownList ID="DropDownList2" runat="server" />
                    </ContentTemplate>
                </asp:UpdatePanel>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label2" runat="server" Text="Label" />
            </ItemTemplate>
        </asp:TemplateField>
        <asp:CommandField ShowEditButton="True" />
    </Columns>
</asp:GridView>

How to get reference of DropDownList2 in DropDownList1_SelectedIndexChanged when grid is in edit mode?

Answer 1

After editing your question. you can achieve like…

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
    DropDownList DropDownList2 = ((DropDownList)((DropDownList)sender).Parent.FindControl("DropDownList2"));
}