网上的很多PHP微信扫码支付接入教程都颇为复杂，且需要配置和引入较多的文件，本人通过整理后给出一个单文件版的，只有200行代码，希望可以给各位想接入微信扫码支付的带来些许帮助和借鉴意义。

直接运行该文件即可得到一个支付二维码的图片。

需要注意的事项： 
1.该文件需放到支付授权目录下，可以在微信支付商户平台->产品中心->开发配置中设置。 
2.如提示签名错误可以通过微信支付签名验证工具进行验证：https://pay.weixin.qq.com/wiki/tools/signverify/

代码如下：

<?php header('Content-type:text/html; Charset=utf-8'); $mchid = 'xxxxx'; //微信支付商户号 PartnerID 通过微信支付商户资料审核后邮件发送 $appid = 'xxxxx'; //公众号APPID 通过微信支付商户资料审核后邮件发送 $apiKey = 'xxxxx'; //https://pay.weixin.qq.com 帐户设置-安全设置-API安全-API密钥-设置API密钥 $wxPay = new WxpayService($mchid,$appid,$apiKey); $outTradeNo = uniqid(); //你自己的商品订单号 $payAmount = 0.01; //付款金额，单位:元 $orderName = '支付测试'; //订单标题 $notifyUrl = 'https://www.xxx.com/wx/'; //付款成功后的回调地址(不要有问号) $payTime = time(); //付款时间 $arr = $wxPay->createJsBizPackage($payAmount,$outTradeNo,$orderName,$notifyUrl,$payTime); //生成二维码 $url = 'http://qr.liantu.com/api.php?text='.$arr['code_url']; echo "<img src='{$url}' style='width:300px;'>"; class WxpayService { protected $mchid; protected $appid; protected $apiKey; public function __construct($mchid, $appid, $key) { $this->mchid = $mchid; $this->appid = $appid; $this->apiKey = $key;
    } /**
     * 发起订单
     * @param float $totalFee 收款总费用 单位元
     * @param string $outTradeNo 唯一的订单号
     * @param string $orderName 订单名称
     * @param string $notifyUrl 支付结果通知url 不要有问号
     * @param string $timestamp 订单发起时间
     * @return array
     */ public function createJsBizPackage($totalFee, $outTradeNo, $orderName, $notifyUrl, $timestamp) { $config = array( 'mch_id' => $this->mchid, 'appid' => $this->appid, 'key' => $this->apiKey,
        ); $orderName = iconv('GBK','UTF-8',$orderName); $unified = array( 'appid' => $config['appid'], 'attach' => 'pay', //商家数据包，原样返回，如果填写中文，请注意转换为utf-8 'body' => $orderName, 'mch_id' => $config['mch_id'], 'nonce_str' => self::createNonceStr(), 'notify_url' => $notifyUrl, 'out_trade_no' => $outTradeNo, 'spbill_create_ip' => '127.0.0.1', 'total_fee' => intval($totalFee * 100), //单位 转为分 'trade_type' => 'NATIVE',
        ); $unified['sign'] = self::getSign($unified, $config['key']); $responseXml = self::curlPost('https://api.mch.weixin.qq.com/pay/unifiedorder', self::arrayToXml($unified)); $unifiedOrder = simplexml_load_string($responseXml, 'SimpleXMLElement', LIBXML_NOCDATA); if ($unifiedOrder === false) { die('parse xml error');
        } if ($unifiedOrder->return_code != 'SUCCESS') { die($unifiedOrder->return_msg);
        } if ($unifiedOrder->result_code != 'SUCCESS') { die($unifiedOrder->err_code);
        } $codeUrl = (array)($unifiedOrder->code_url); if(!$codeUrl[0]) exit('get code_url error'); $arr = array( "appId" => $config['appid'], "timeStamp" => $timestamp, "nonceStr" => self::createNonceStr(), "package" => "prepay_id=" . $unifiedOrder->prepay_id, "signType" => 'MD5', "code_url" => $codeUrl[0],
        ); $arr['paySign'] = self::getSign($arr, $config['key']); return $arr;
    } public function notify() { $config = array( 'mch_id' => $this->mchid, 'appid' => $this->appid, 'key' => $this->apiKey,
        ); $postStr = $GLOBALS["HTTP_RAW_POST_DATA"]; $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA); if ($postObj === false) { die('parse xml error');
        } if ($postObj->return_code != 'SUCCESS') { die($postObj->return_msg);
        } if ($postObj->result_code != 'SUCCESS') { die($postObj->err_code);
        } $arr = (array)$postObj; unset($arr['sign']); if (self::getSign($arr, $config['key']) == $postObj->sign) { echo '<xml><return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg></xml>'; return $postObj;
        }
    } /**
     * curl get
     *
     * @param string $url
     * @param array $options
     * @return mixed
     */ public static function curlGet($url = '', $options = array()) { $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30); if (!empty($options)) {
            curl_setopt_array($ch, $options);
        } //https请求 不验证证书和host curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false); $data = curl_exec($ch);
        curl_close($ch); return $data;
    } public static function curlPost($url = '', $postData = '', $options = array()) { if (is_array($postData)) { $postData = http_build_query($postData);
        } $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30); //设置cURL允许执行的最长秒数 if (!empty($options)) {
            curl_setopt_array($ch, $options);
        } //https请求 不验证证书和host curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false); $data = curl_exec($ch);
        curl_close($ch); return $data;
    } public static function createNonceStr($length = 16) { $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'; $str = ''; for ($i = 0; $i < $length; $i++) { $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        } return $str;
    } public static function arrayToXml($arr) { $xml = "<xml>"; foreach ($arr as $key => $val) { if (is_numeric($val)) { $xml .= "<" . $key . ">" . $val . "</" . $key . ">";
            } else $xml .= "<" . $key . "><![CDATA[" . $val . "]]></" . $key . ">";
        } $xml .= "</xml>"; return $xml;
    } /**
     * 获取签名
     */ public static function getSign($params, $key) { ksort($params, SORT_STRING); $unSignParaString = self::formatQueryParaMap($params, false); $signStr = strtoupper(md5($unSignParaString . "&key=" . $key)); return $signStr;
    } protected static function formatQueryParaMap($paraMap, $urlEncode = false) { $buff = "";
        ksort($paraMap); foreach ($paraMap as $k => $v) { if (null != $v && "null" != $v) { if ($urlEncode) { $v = urlencode($v);
                } $buff .= $k . "=" . $v . "&";
            }
        } $reqPar = ''; if (strlen($buff) > 0) { $reqPar = substr($buff, 0, strlen($buff) - 1);
        } return $reqPar;
    }
}