phpqrcode cannot output QR code

<span>header</span>('Content-Type: image/png'<span>);
</span><span>include_once</span> 'phpqrcode/qrlib.php'<span>;
</span><span>$a</span> = "http://www.play17.cn/play/wlogin.html"<span>;
</span><span>ob_clean</span><span>();
QRcode</span>::png(<span>$a</span>);

Add output type

<span>header</span>('Content-Type: image/png');

Clear cache ob_clean()

<span>ob_clean</span>();

The above introduces that phpqrcode cannot output QR codes, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.