class WxpayService
{
protected $mchid;
protected $appid;
protected $apiKey;

public function __construct($mchid,$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,$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,);
$postStr = $GLOBALS["HTTP_RAW_POST_DATA"];

$postObj = simplexml_load_string($postStr,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_POST,CURLOPT_POSTFIELDS,$postData);
curl_setopt($ch,30); //设置cURL允许执行的最长秒数
if (!empty($options)) {
curl_setopt_array($ch,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)
{
$xml = "";
foreach ($arr as $key => $val) {
if (is_numeric($val)) {
$xml .= "<" . $key . ">" . $val . "</" . $key . ">";
} else
$xml .= "<" . $key . "><![CDATA[" . $val . "]]></" . $key . ">";
}
$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,strlen($buff) - 1);
}
return $reqPar;
}
}