1. composer安装qrcode

composer require 2amigos/qrcode-library

2. 生成二维码

use Da\QrCode\QrCode;

public function getCode($code)
{
    $dir = iconv("UTF-8", "GBK", './qrcode');
    mkdir($dir, 0777, true);

    $url = Yii::$app->request->hostInfo . '/area?code=' . $code;  //二维码内容自定义
    $qrCode = (new QrCode($url))
        ->setSize(250)
        ->setMargin(5)
        // ->setForegroundColor(51, 153, 255)
        // ->setBackgroundColor(51, 153, 255)
        ->writeFile(Yii::$app->basePath . '/web/qrcode/' . $code . '.png');
}

 3.打包文件夹并下载 

<?php

namespace app\libs;

class downLoadZip
{
    public function downLoadFiles()
    {
        $exportPath = './qrcode';
        $filename = $exportPath . '.zip';
        $zip = new \ZipArchive();
        //参数1:zip保存路径，参数2：ZIPARCHIVE::CREATE没有即是创建
        if (!$zip->open($filename, \ZIPARCHIVE::CREATE)) {
            echo "创建[exportPath.zip]失败<br/>";
            return;
        }
        //echo "创建[$exportPath.zip]成功<br/>";
        $this->createZip(opendir($exportPath), $zip, $exportPath);
        $zip->close();

        header("Cache-Control: public");
        header("Content-Description: File Transfer");
        header('Content-disposition: attachment; filename=' . basename($filename)); //文件名
        header("Content-Type: application/zip"); //zip格式的
        header("Content-Transfer-Encoding: binary"); //告诉浏览器，这是二进制文件
        header('Content-Length: ' . filesize($filename)); //告诉浏览器，文件大小

        $this->deldir('./qrcode');
        @readfile($filename);
        unlink('qrcode.zip'); //删除服务器压缩文件,释放服务器资源
    }


    function createZip($openFile, $zipObj, $sourceAbso, $newRelat = '')
    {
        while (($file = readdir($openFile)) != false) {
            if ($file == "." || $file == "..")
                continue;

            /*源目录路径(绝对路径)*/
            $sourceTemp = $sourceAbso . '/' . $file;
            /*目标目录路径(相对路径)*/
            $newTemp = $newRelat == '' ? $file : $newRelat . '/' . $file;
            if (is_dir($sourceTemp)) {
                //echo '创建'.$newTemp.'文件夹<br/>';
                $zipObj->addEmptyDir($newTemp);/*这里注意：php只需传递一个文件夹名称路径即可*/
                $this->createZip(opendir($sourceTemp), $zipObj, $sourceTemp, $newTemp);
            }
            if (is_file($sourceTemp)) {
                //echo '创建'.$newTemp.'文件<br/>';
                $zipObj->addFile($sourceTemp, $newTemp);
            }
        }
    }

    public function deldir($dir)
    {
        //先删除目录下的文件：
        $dh = opendir($dir);
        while ($file = readdir($dh)) {
            if ($file != "." && $file != "..") {
                $fullpath = $dir . "/" . $file;
                if (!is_dir($fullpath)) {
                    unlink($fullpath);
                } else {
                    $this->deldir($fullpath);
                }
            }
        }
    }
}