สอบถามปัญหา Crystal Reports Close and Dispose Error "Object reference not set to an instance of an object."

    Rpt.Close()
    Rpt.Dispose()

Protected Sub Page_Unload(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Unload
        If ViewState("Show_Report") = "True" Then
            crReportDoc.Close()
            crReportDoc.Dispose()
            GC.Collect()
        End If
End Sub