show and hide based on a text box.txt

   Protected Sub btnFive_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnFive.Click
      Dim numberOf As Integer = 0
      If String.IsNullOrEmpty(txtNumberOf.Text) = False Then 'Takes the value from a text box and stores it for the looping
         Integer.TryParse(txtNumberOf.Text, numberOf)
         If numberOf > -1 Then 'Allows zero to be an inputted value
            showHideBoxes(numberOf)
         End If
      End If
   End Sub

   Private Sub showHideBoxes(ByVal num As Integer)
      Dim c As Control
      Dim i As Integer
      'Loop 1 identifies and hides all boxes
      For i = 1 To 9 'End Point is hard coded to total number of boxes we want to hide
         c = Page.FindControl("TextBox" + i.ToString) 'Finds a control labeled Textbox1, and so on for the value of i
         If TypeOf c Is TextBox Then 'Prevents the form from failing
            c.Visible = False 
         End If
      Next 'Continue to loop 2 to flip the desired number of boxes 
      If num > 0 Then
         For i = 1 To num
            c = Page.FindControl("TextBox" + i.ToString)
            If TypeOf c Is TextBox Then
               c.Visible = True
            End If
         Next
      End If

   End Sub

   Private Sub readOnlyFlip(ByVal num As Integer)
      Dim c As UI.WebControls.TextBox
      Dim i As Integer
      'Dim txtBox As Control
      For i = 1 To 27 'This will change once we work out the math for determining the columns selected. 
         c = Page.FindControl("TextBox" + i.ToString)
         'Dim txtBox = c, Type("TextBox")
         If TypeOf c Is TextBox Then
            'c.Attributes.Add("readonly", "readonly")
            c.ReadOnly = True
            c.BackColor = Drawing.Color.WhiteSmoke
         End If
      Next
      If num > 0 Then
         For i = 1 To num
            c = Page.FindControl("TextBox" + i.ToString)
            'Dim txtBox = c, Type("TextBox")
            If TypeOf c Is TextBox Then
               'c.Attributes.Add("readonly", "readonly")
               c.ReadOnly = False
               c.BackColor = Drawing.Color.White
            End If
         Next
      End If

   End Sub