?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'; //微信支付申请对应的公众号的APPID
$appKey = 'xxxxx'; //微信支付申请对应的公众号的APP Key
$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

//①、获取用户openid
$wxPay = new WxpayService($mchid,$appid,$appKey,$apiKey);
$openId = $wxPay->GetOpenid();  //获取openid
if(!$openId) exit('获取openid失败');
//②、统一下单
$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
$jsApiParameters = $wxPay->createJsBizPackage($openId,$payAmount,$outTradeNo,$orderName,$notifyUrl,$payTime);
$jsApiParameters = json_encode($jsApiParameters);
?>
 html>
 head>
  meta charset="utf-8" />
  meta name="viewport" content="width=device-width, initial-scale=1"/>
  title>微信支付样例-支付/title>
  script type="text/javascript">
   //调用微信JS api 支付
   function jsApiCall()
   {
    WeixinJSBridge.invoke(
     'getBrandWCPayRequest',
     ?php echo $jsApiParameters; ?>,
     function(res){
      WeixinJSBridge.log(res.err_msg);
      alert(res.err_code+res.err_desc+res.err_msg);
     }
    );
   }
   function callpay()
   {
    if (typeof WeixinJSBridge == "undefined"){
     if( document.addEventListener ){
      document.addEventListener('WeixinJSBridgeReady', jsApiCall, false);
     }else if (document.attachEvent){
      document.attachEvent('WeixinJSBridgeReady', jsApiCall);
      document.attachEvent('onWeixinJSBridgeReady', jsApiCall);
     }
    }else{
     jsApiCall();
    }
   }
  /script>
 /head>
 body>
 br/>
 font color="#9ACD32">b>该笔订单支付金额为span style="color:#f00;font-size:50px">?php echo $payAmount?>元/span>钱/b>/font>br/>br/>
 div align="center">
  button style="width:210px; height:50px; border-radius: 15px;background-color:#FE6714; border:0px #FE6714 solid; cursor: pointer; color:white; font-size:16px;" type="button" onclick="callpay()" >立即支付/button>
 /div>
 /body>
 /html>
?php
class WxpayService
{
 protected $mchid;
 protected $appid;
 protected $appKey;
 protected $apiKey;
 public $data = null;

 public function __construct($mchid, $appid, $appKey,$key)
 {
  $this->mchid = $mchid; //https://pay.weixin.qq.com 产品中心-开发配置-商户号
  $this->appid = $appid; //微信支付申请对应的公众号的APPID
  $this->appKey = $appKey; //微信支付申请对应的公众号的APP Key
  $this->apiKey = $key; //https://pay.weixin.qq.com 帐户设置-安全设置-API安全-API密钥-设置API密钥
 }

 /**
  * 通过跳转获取用户的openid，跳转流程如下：
  * 1、设置自己需要调回的url及其其他参数，跳转到微信服务器https://open.weixin.qq.com/connect/oauth2/authorize
  * 2、微信服务处理完成之后会跳转回用户redirect_uri地址，此时会带上一些参数，如：code
  * @return 用户的openid
  */
 public function GetOpenid()
 {
  //通过code获得openid
  if (!isset($_GET['code'])){
   //触发微信返回code码
   $scheme = $_SERVER['HTTPS']=='on' ? 'https://' : 'http://';
   $baseUrl = urlencode($scheme.$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF'].$_SERVER['QUERY_STRING']);
   $url = $this->__CreateOauthUrlForCode($baseUrl);
   Header("Location: $url");
   exit();
  } else {
   //获取code码，以获取openid
   $code = $_GET['code'];
   $openid = $this->getOpenidFromMp($code);
   return $openid;
  }
 }

 /**
  * 通过code从工作平台获取openid机器access_token
  * @param string $code 微信跳转回来带上的code
  * @return openid
  */
 public function GetOpenidFromMp($code)
 {
  $url = $this->__CreateOauthUrlForOpenid($code);
  $res = self::curlGet($url);
  //取出openid
  $data = json_decode($res,true);
  $this->data = $data;
  $openid = $data['openid'];
  return $openid;
 }

 /**
  * 构造获取open和access_toke的url地址
  * @param string $code，微信跳转带回的code
  * @return 请求的url
  */
 private function __CreateOauthUrlForOpenid($code)
 {
  $urlObj["appid"] = $this->appid;
  $urlObj["secret"] = $this->appKey;
  $urlObj["code"] = $code;
  $urlObj["grant_type"] = "authorization_code";
  $bizString = $this->ToUrlParams($urlObj);
  return "https://api.weixin.qq.com/sns/oauth2/access_token?".$bizString;
 }

 /**
  * 构造获取code的url连接
  * @param string $redirectUrl 微信服务器回跳的url，需要url编码
  * @return 返回构造好的url
  */
 private function __CreateOauthUrlForCode($redirectUrl)
 {
  $urlObj["appid"] = $this->appid;
  $urlObj["redirect_uri"] = "$redirectUrl";
  $urlObj["response_type"] = "code";
  $urlObj["scope"] = "snsapi_base";
  $urlObj["state"] = "STATE"."#wechat_redirect";
  $bizString = $this->ToUrlParams($urlObj);
  return "https://open.weixin.qq.com/connect/oauth2/authorize?".$bizString;
 }

 /**
  * 拼接签名字符串
  * @param array $urlObj
  * @return 返回已经拼接好的字符串
  */
 private function ToUrlParams($urlObj)
 {
  $buff = "";
  foreach ($urlObj as $k => $v)
  {
   if($k != "sign") $buff .= $k . "=" . $v . "";
  }
  $buff = trim($buff, "");
  return $buff;
 }

 /**
  * 统一下单
  * @param string $openid 调用【网页授权获取用户信息】接口获取到用户在该公众号下的Openid
  * @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 $timestamp 支付时间
  * @return string
  */
 public function createJsBizPackage($openid, $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,
   'openid' => $openid,   //rade_type=JSAPI，此参数必传
   'out_trade_no' => $outTradeNo,
   'spbill_create_ip' => '127.0.0.1',
   'total_fee' => intval($totalFee * 100),  //单位 转为分
   'trade_type' => 'JSAPI',
  );
  $unified['sign'] = self::getSign($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);
  }
  $arr = array(
   "appId" => $config['appid'],
   "timeStamp" => "$timestamp",  //这里是字符串的时间戳，不是int，所以需加引号
   "nonceStr" => self::createNonceStr(),
   "package" => "prepay_id=" . $unifiedOrder->prepay_id,
   "signType" => 'MD5',
  );
  $arr['paySign'] = self::getSign($arr, $config['key']);
  return $arr;
 }

 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 . ">";
  }
  $xml .= "/xml>";
  file_put_contents('1.txt',$xml);
  return $xml;
 }

 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;
 }
}
?>