Open Illustrator file vb.net

   Public Sub IllustratorOpen()

        Dim illApp = CreateObject("Illustrator.Application")

        Dim FullPath = "C:\temp\testTemp\test.ai"

        With illApp.Open(FullPath)

            .Activate()

            'Check TextFrames

            For Each textFrame As Object In .TextFrames

                MsgBox(textFrame.Contents)

            Next

            'Check Layers

            For Each layer As Object In .Layers

                MsgBox(layer.Name)

                layer.Visible = True

            Next

            'aiDoNotSaveChanges = 2

            .Close(2)

        End With

        illApp.Quit()

        illApp = Nothing

    End Sub