Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button1.Click
        For Each C As Control In Me.Panel2.Controls
            machwas(C)
        Next
        For Each C As Control In Me.Panel7.Controls
            machwas(C)
        Next
End Sub
 
Private Sub machwas(ByVal C As Control)
        If TypeOf C Is TextBox Then
            ' Code
        End If
End Sub