<"service" => "create_direct_pay_by_user",
      "partner" => trim($this->alipay_config['partner']),
      "payment_type"  => '1',
      "notify_url"  => site_url('alipay/do_notify'),
      "return_url"  => site_url('alipay/do_return'),
      "seller_email"  => trim($this->alipay_config['seller_emaill']),//支付宝帐户,
      "out_trade_no"  => $this->input->post('WIDout_trade_no'),//商户订单号
      "subject"  => $this->input->post('WIDsubject'),//订单名称
      "total_fee"  => $this->input->post('WIDtotal_fee'),//必填,付款金额
      "body"  => $this->input->post('WIDbody'),//必填,订单描述
      "show_url"  => $this->input->post('WIDshow_url'),//商品展示地址
      "anti_phishing_key"  => '',//防钓鱼时间戳
      "exter_invoke_ip"  => '',//客户端的IP地址
      "_input_charset"  => trim(strtolower($this->alipay_config['input_charset']))
    );
    //建立请求
    $alipaySubmit = new AlipaySubmit($this->alipay_config);
    $html_text = $alipaySubmit->buildRequestForm($parameter,"get", "确认");
    echo $html_text;
  }
  function do_notify(){
    require_once(APPPATH.'third_party/alipay/alipay_notify.class.php');
  }
  function do_return(){
    require_once(APPPATH.'third_party/alipay/alipay_notify.class.php');
    $alipayNotify = new AlipayNotify($this->alipay_config);
    $verify_result = $alipayNotify->verifyReturn();
    //商户订单号
    $out_trade_no = $_GET['out_trade_no'];
    //支付宝交易号
    $trade_no = $_GET['trade_no'];
    //交易状态
    $trade_status = $_GET['trade_status'];
    if($_GET['trade_status'] == 'TRADE_FINISHED' || $_GET['trade_status'] == 'TRADE_SUCCESS') {
      //判断该笔订单是否在商户网站中已经做过处理
      //如果没有做过处理，根据订单号（out_trade_no）在商户网站的订单系统中查到该笔订单的详细，并执行商户的业务程序
      //如果有做过处理，不执行商户的业务程序
      echo '支付成功，交易处理环节';
    }else {
      echo "trade_status=".$_GET['trade_status'];
    }
    echo "验证成功<br />";
  }
  /**
   * 初始化支付宝配置，详细参数请根据自己实际接口修改
   */
  private function _init_config(){
    //支付宝帐户
    $alipay_config['seller_emaill'] = ''; 
    //合作身份者id，以2088开头的16位纯数字
    $alipay_config['partner'] = '2088999999999999';
    //安全检验码，以数字和字母组成的32位字符
    $alipay_config['key'] = 'vhyjvdht3ayxbtx692vlkbwilhXXXXXX';
    //签名方式 不需修改
    $alipay_config['sign_type'] = strtoupper('MD5');
    //字符编码格式 目前支持 gbk 或 utf-8
    $alipay_config['input_charset'] = strtolower('utf-8');
    //ca证书路径地址，用于curl中ssl校验
    //请保证cacert.pem文件在当前文件夹目录中
    $alipay_config['cacert'] = APPPATH.'third_party/alipay/cacert.pem';
    //访问模式,根据自己的服务器是否支持ssl访问，若支持请选择https；若不支持请选择http
    $alipay_config['transport'] = 'http';
    $this->alipay_config = $alipay_config;
  }
}