label in popup isnot appearing as expected

Question

User-1767698477 posted

I have a popup which appears and allows to edit or add a new row to database. I have a dropdown called ddgiftsource which when the index number 6 is selected (Other Source) they have to complete the textbox Othersource.  So just before completing the code to save the details to the database, I have:

 Protected Sub btn2Insert_Click(ByVal sender As Object, ByVal e As EventArgs)
        If ddgiftsource.SelectedIndex = 6 Then
            If txtothersource.Text = "" Then
                lblerror.Visible = True
                Exit Sub
            End If
        End If

The popup is just closing upon reaching Exit Sub and the message in the label is not appearing or if it is appearing, it is not viewable since the box closes. The message needs to appear and the box should stay open. Why isn't this happening now? Below is the last row of the popup.

 <tr>
                                <td colspan="4" align="center">
                                    <asp:Label ID="lblerror" runat="server" ForeColor="Red" Text="If you select Other Source, you must<br /> complete the Other Source field" Font-Bold="true" Width="300px"></asp:Label><br />
                                    <asp:HiddenField ID="HiddenField2" runat="server" />
                                    <asp:Button ID="btn2Update" CommandName="Update" runat="server" Text="Update" OnClick="btn2Update_Click" CausesValidation="False" />
                                    <asp:Button ID="btn2Insert" CommandName="Insert" runat="server" Text="Add" OnClick="btn2Insert_Click" CausesValidation="False" />
                                    <asp:Button ID="btn2Cancel" runat="server" Text="Cancel" />
                                </td>
                                <td></td>
                                <td></td>
                                <td></td>
                            </tr>
                        </table>

Answer 1

User-943250815 posted

Have in mind all buttons 3 button in your code does a PostBack, so your page is recreated at every click.
Usually a Popup is hidden on page load then after some action like a button click it is switched to show/pop.