How to retrieve back editable values in textboxes added in PlaceHolder?

[mlco]

I'm a newbie here and I'm stuck with the coding. So far I've created 3 buttons, first button is to load the values in textboxes added to placeholder. Then button2 is to extract the data from button 1 and display out. Now the 3rd step, I want to edit the values from the textboxes, after edit, how do I grab and display out the new values in label and textboxes?

Partial Class _Default
    Inherits System.Web.UI.Page

    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim x As Integer = 1
        Dim message As String

        For x = 1 To 36
            Dim txt As New TextBox
            'txt.ID = "Text" & ViewState("COUNT")
            txt.ID = "Text" & x
            txt.Text = x.ToString
            PlaceHolder1.Controls.Add(txt)
        Next


        For x = 1 To 36
            Dim stxt As String = "Text" & x.ToString
            Dim txtxx As TextBox = TryCast(PlaceHolder1.FindControl(stxt), TextBox)
            If txtxx IsNot Nothing Then
                'There's your textbox value.
                message = message & txtxx.Text & ","
            End If
        Next
        'Label1.Text = message
        Session("message") = message
    End Sub

Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click

        Label1.Text = Session("message")

        Dim x As Integer
        Dim message As String = ""

        For x = 1 To 36
            Dim txt As New TextBox

            txt.ID = "Text" & x
            txt.Text = x.ToString
            PlaceHolder1.Controls.Add(txt)
        Next

        For x = 1 To 36
            Dim stxt As String = "Text" & x.ToString
            Dim txtxx As TextBox = TryCast(PlaceHolder1.FindControl(stxt), TextBox)
            If txtxx IsNot Nothing Then
                'There() 's your textbox value.
                message = message & txtxx.Text
            End If
        Next

    End Sub

    Protected Sub Button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button3.Click

    End Sub

End Class