VB.Net จะดึงค่าจาก Textbox ที่สร้างจาก as new textbox ไปใส่ใน Array อย่างไร

dim z(100,100)
     Dim s = 0
        For x = 1 To CInt(tbxRow.Text)
            Dim l = 0
            For y = 1 To CInt(tbxColumn.Text)
                Dim textbox As New TextBox
                textbox.Name = x & "," & y
                Dim b = New Point(50, 50)
                textbox.Bounds = New Rectangle(b, New Size(100, 100))
                textbox.Location = New Point(30 + s, 130 + 25 + l)
                textbox.Size = New Size(50, 20)
                Me.Controls.Add(textbox)
                l += 25
                z(1, y) = CInt(tbxColumn.Text)
            Next
            s = 60 * x
        Next