在调用“JSAPI下单”接口/v3/pay/transactions/jsapi 时响应内容里提示：“输入源“/appid”映射到字段“公众号I (truncated...)” 我确认我填写的appid是小程序的不是公众号的，使用的是官方的wechatpay-apiv3/wechatpay-php sdk,核心代码如下：     // 获取预支付id     public static function orderInfo($p){         $url = 'https://api.mch.weixin.qq.com/v3/pay/transactions/jsapi';         // $url = '/v3/pay/transactions/jsapi';         $appId = Config::WxAppId;         $mchId = Config::WxMchId;         $mchName = Config::WxMchName;         $serial_no = Config::WxPayCartNo;         $orderNo = dechex(time()) . rand(1000, 9999);         $notify_url = Config::Host . Config::BasePath . '/wechat/payNotify';         $score = $p['score'];         $openId = '我自己的openid';         // 从本地文件中加载「商户API私钥」，「商户API私钥」会用来生成请求的签名         $merchantPrivateKey = file_get_contents(SS_PLUGIN_APP_DIR.'/certs/apiclient_key.pem');         $merchantPrivateKeyInstance = Rsa::from($merchantPrivateKey, Rsa::KEY_TYPE_PRIVATE);         // 从本地文件中加载「微信支付平台证书」，用来验证微信支付应答的签名         $platformCertificate = file_get_contents(SS_PLUGIN_APP_DIR.'/certs/apiclient_cert.pem');         $platformPublicKeyInstance = Rsa::from($platformCertificate, Rsa::KEY_TYPE_PUBLIC);         // 从「微信支付平台证书」中获取「证书序列号」         $platformCertificateSerial = PemUtil::parseCertificateSerialNo($platformCertificate);         // 构造一个 APIv3 客户端实例         $instance = Builder::factory([             'mchid'      => $mchId,             'serial'     => $serial_no,             'privateKey' => $merchantPrivateKeyInstance,             'certs'      => [                 $platformCertificateSerial => $platformPublicKeyInstance,             ],         ]);                 $data = array(             "appid" => $appId,             "mchid" => $mchId,             "description" => "$mchName-积分充值-$score",             "out_trade_no" => $orderNo,             "time_expire" => time() + 600,             "attach" => "自定义数据说明",             "notify_url" => $notify_url,             "amount" => array(                 "total" => $p['price'],                 "currency" => "CNY"             ),             "payer" => array(                 "openid" => $openId             )         );         try{             $rep = $instance->chain($url)->post($data)->getBody();             return json_decode($rep);         }catch(Exception $e){             $code = $e->getCode();             return array('code' => $code, 'rep' => $e->getMessage(), 'req' => $data);         }     } // $e->getMessage()： 'Client error: `POST https://api.mch.weixin.qq.com/v3/pay/transactions/jsapi` resulted in a `400 Bad Request` response:\n{"code":"PARAM_ERROR","detail":{"location":null,"value":""},"message":"输入源“/appid”映射到字段“公众号I (truncated...)\n' [图片] [图片]