use Endroid\QrCode\ErrorCorrectionLevel;
use Endroid\QrCode\QrCode;
$code = 'www.baidu.com';
$qrCode = new QrCode($code);
$qrCode->setSize(300);
$qrCode->setWriterByName('png');
$qrCode->setMargin(10);
$qrCode->setEncoding('UTF-8');
$qrCode->setErrorCorrectionLevel(ErrorCorrectionLevel::HIGH);
$qrCode->setForegroundColor(['r' => 0, 'g' => 0, 'b' => 0, 'a' => 0]);
$qrCode->setBackgroundColor(['r' => 255, 'g' => 255, 'b' => 255, 'a' => 0]);
$qrCode->setValidateResult(false);
//header('Content-Type: '.$qrCode->getContentType());
//echo $qrCode->writeString() ;
$str = base64_encode($qrCode->writeString());
composer引入组件composer require endroid/qr-code
如上调用就可以生成二维码的图片码，打开注释并注释最后一行，就可以在浏览器输出二维码
composer qr-code查看文档地址：
https://packagist.org/packages/endroid/qr-code
