Partial Class _Default
    Inherits System.Web.UI.Page
 
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As _
      System.EventArgs) Handles Me.Load
        If Not IsPostBack Then
            'kein Postback
            Dim t As New TextBox
            t.ID = "testID"
            Me.Panel1.Controls.Add(t)
        Else
            'Postback
            Dim t As New TextBox
            t.ID = "testID"
            Me.Panel1.Controls.Add(t)
        End If
    End Sub
 
    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        'Hier kommt dein SQL-Code rein
    End Sub
End Class