thinkPHP5 生成微信小程序二维码 保存在本地

PHP生成微信小程序二维码需要注意两点：

　　1、小程序必须是上线的

　　2、传入二维码中需要跳转的小程序页面路径最前面不能加‘/’

具体实现代码如下：

<?php

namespace app\admin\controller;

use think\facade\Env;
use app\admin\model\Company;

class Index extends Common {
    
    public function index() {
        $res = 1;
        $qrcode = self::getQrcode($res,'pages/index/index');
        dump($qrcode);
    }
    /**
     * 获取小程序二维码
     * @param int $good_id                  商品ID
     * @param varchar $samll_program_url    要跳转的路径（小程序路径）
     */ 
    protected static function getQrcode($good_id,$samll_program_url)
    {
        require_once(Env::get('root_path') . 'vendor/Other/JSSDK.php');
        
        $filename = "qrcode_" . $good_id . ".jpg";//要生成的图片名字

        $IMG_PATH = config('app.public.qrcode');//保存服务器路径
        $shop_url = config('app.public.host');//网址
        if (file_exists('./'.$IMG_PATH .'/'. $filename)) { //存在返回图片路径
            return $shop_url . $IMG_PATH .'/'. $filename;
        }

        $jssdk = new \JSSDK(config('app.wxapp.app_id'), config('app.wxapp.app_secret'));
        $access_token = $jssdk->getAccessTokenMinProgram();
        $scene = $good_id;
        $data = '{"scene":"' . $scene . '","page":"' . $samll_program_url . '","width":280}';
        $jpg = posturl('https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token=' . $access_token, $data);//二进制原始数据
        
        $res = file_put_contents('./'.$IMG_PATH .'/'. $filename,$jpg);

        return $shop_url . $IMG_PATH .'/'. $filename;
    }
}

JSSDK.php文件内容如下：

<?php

class JSSDK {
    private $appId;
    private $appSecret;

    public function __construct($appId, $appSecret) {
        $this->appId = $appId;
        $this->appSecret = $appSecret;
    }

    public function getSignPackage($url = null) {
        $jsapiTicket = $this->getJsApiTicket();
        // 注意 URL 一定要动态获取，不能 hardcode.
        if($url === null)
        {
            if (isset($_SERVER['HTTP_REFERER'])) {
                $url = $_SERVER['HTTP_REFERER'];
            } else {
                $url = '';
            }
        }
        $timestamp = time();
        $nonceStr = $this->createNonceStr();

        // 这里参数的顺序要按照 key 值 ASCII 码升序排序
        $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";

        $signature = sha1($string);

        $signPackage = array(
            "app_id"     => $this->appId,
            "nonceStr"  => $nonceStr,
            "timestamp" => $timestamp,
            "url"       => $url,
            "signature" => $signature,
            "rawString" => $string
        );
        return $signPackage; 
    }

    private function createNonceStr($length = 16) {
        $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        $str = "";
        for ($i = 0; $i < $length; $i++) {
        $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }

    private function getJsApiTicket() {
    
        $accessToken = $this->getAccessToken();
        // 如果是企业号用以下 URL 获取 ticket
        // $url = "https://qyapi.weixin.qq.com/cgi-bin/get_jsapi_ticket?access_token=$accessToken";
        $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=$accessToken";
        $res = json_decode($this->getUrl($url),true);
        if (isset($res['ticket'])) {
            $ticket = $res['ticket'];     
        } else {
            $ticket = '';
        }
    
        return $ticket;
    }

    public function getAccessToken() {

        if ($access_token = Cache::get("access_token")) {
            return $access_token;
        }
    
        // 如果是企业号用以下URL获取access_token
        // $url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=$this->appId&corpsecret=$this->appSecret";
        $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";

        $res = json_decode($this->getUrl($url),true);

        if (isset($res["access_token"])) {
            $access_token = $res["access_token"];    
            return $access_token;
        } else {        
            return '';
        }    
    
    }

    public function getAccessTokenMinProgram() {

        if ($access_token = Cache::get("access_token_min_program")) {
            return $access_token;
        }
        // 如果是企业号用以下URL获取access_token
        // $url = "https://qyapi.weixin.qq.com/cgi-bin/gettoken?corpid=$this->appId&corpsecret=$this->appSecret";
        $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$this->appId&secret=$this->appSecret";
        $res = json_decode($this->getUrl($url),true);

        if (isset($res["access_token"])) {
            $access_token = $res["access_token"];
            return $access_token;
        } else {
            return '';
        }

    }
    private function getUrl($url){
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        $output = curl_exec($ch);
        curl_close($ch);
        return $output;
    }

}

注：如果file_put_contents()报错，请先检查文件夹是否创建以及是否有写入的权限；其次再检查文件路径是否正确。