Get a Value from dynamically created Textbox

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Not IsPostBack Then
            Session("count") = 0
            Dim table As Table = New Table()

            table.ID = "Tab1"
            Page.Form.Controls.Add(table)
            Dim i As Integer
            For i = 0 To 3
                Dim text As TextBox = New TextBox()
                text.ID = "text_" & i

                Page.Form.Controls.Add(New TextBox())
            Next
            Session("count") = Session("count") + 1
        End If
    End Sub

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click

Dim ds As DataTable = New DataTable()
        ds.Columns.Add("Textboxid")
        Dim tab As Table = New Table()
        tab.ID = "Table1"
        Page.Form.Controls.Add(tab)
        Dim too As Integer = Session("count")

        For i = 0 To too
            Dim row As TableRow = New TableRow()
            For j = 0 To 3
                Dim cell As TableCell = New TableCell()
                Dim textb As TextBox = New TextBox()
                textb.ID = "text_" & i & "Col" & j
                ds.Rows.Add(textb.ID)
                cell.Controls.Add(textb)
                row.Cells.Add(cell)
            Next

            tab.Rows.Add(row)
        Next
        Session("count") = Session("count") + 1
        Session("dataTable") = ds
    End Sub

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

-----HERE I WANT CODE WHEN I CLICK THIS BUTTON CONTROL I WANT GET A VALUE FROM DYNAMICALLY CREATED TEXBOX.


 End Sub