Setting properties of aspx controls based in a generic List

I get a generic list of all controls in an aspx page. What I'm trying to do with each element of that list is to set a value for properties Visible and Enabled of those aspx controls.

I don't know how to get TYPE from each element of generic list.

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Dim controlList As New List(Of Control)
        controlList = AddControls(Page.Controls, controlList)
        For Each ctl As Control In controlList
            Response.Write(ctl.ID & "<br/>")

            'Here I setup property Enabled of control textbox1
            CType(Me.FindControl("textbox1"), TextBox).Enabled = True

            'I'd like to setup property Enabled of control ctl.ID, but how to invoke <type of ctl>
            CType(Me.FindControl(ctl.ID), <type of ctl> ).Enabled = True

        Next
    End Sub

    Private Function AddControls(ByVal page As ControlCollection, ByVal controlList As List(Of Control)) As List(Of Control)
        For Each c As Control In page
            If c.ID IsNot Nothing Then
                controlList.Add(c)
            End If

            If c.HasControls() Then
                AddControls(c.Controls, controlList)
            End If
        Next
        Return controlList
    End Function

Select allOpen in new window