มีวิธีอ้างอิง control ระหว่าง runtime หรือป่าวครับ รายละเอียดต่อต่อด้านในครับ...

Imports Microsoft.VisualBasic
Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls
Imports System.Threading
Imports System.Globalization

Public Class BasePage
    Inherits Page

    Public Const LanguageDropDownName As String = "ctl00$cphHeader$Header1$ddlLanguage"
    Public Const PostBackEventTarget As String = "__EVENTTARGET"

    Protected Overrides Sub InitializeCulture()

        If Request(PostBackEventTarget) IsNot Nothing Then

            Dim controlID As String = Request(PostBackEventTarget)

            If controlID.Equals(LanguageDropDownName) Then

                Dim selectedValue As String = Request.Form(Request(PostBackEventTarget)).ToString()

                Select Case selectedValue
                    Case "0"
                        SetCulture("hi-IN", "hi-IN")
                        Exit Select
                    Case "1"
                        SetCulture("en-US", "en-US")
                        Exit Select
                    Case "2"
                        SetCulture("en-GB", "en-GB")
                        Exit Select
                    Case "3"
                        SetCulture("fr-FR", "fr-FR")
                        Exit Select
                    Case Else
                        Exit Select
                End Select

            End If
        End If

    End Sub

    Protected Sub SetCulture(ByVal name As String, ByVal locale As String)
        Thread.CurrentThread.CurrentUICulture = New CultureInfo(name)
        Thread.CurrentThread.CurrentCulture = New CultureInfo(locale)
        Session("MyUICulture") = Thread.CurrentThread.CurrentUICulture
        Session("MyCulture") = Thread.CurrentThread.CurrentCulture
    End Sub