顶部一条线怎么去掉???$pdf = new TCPDF(PDF_PAGE_ORIENTATION, $unit='pt', PDF_PAGE_FORMAT, true, 'UTF-8', false);
$pdf->AddPage();
$pdf->Image('./images/invoice/oxford-summer-school-logo.gif', 40, 38,'' , '', 'GIF');
$pdf->SetXY(40,160);
$pdf->writeHTML("<b>".$invoice_type_value."</b>");
$pdf->Output('example_039.pdf', 'I');
$pdf->setPrintHeader(false);