serverUrl,
            $this->appId,
            $this->partner_private_key,
            $this->format,
            $this->charset
        );
        $response = null;
        $outputStream = null;
        $request = $alipayClient->getContents();
        //200
        //echo( '状态码:'. $request -> getCode() .', ');
        //echo '
';
        $fileType = $request->getType();
        //echo( '类型:'. $fileType .', ');
        if ($fileType == 'text/plain') {
            //出错,返回 json
            echo $request->getBody();
        } else {
            $type = $request->getFileSuffix($fileType);
            //echo $this -> getParams();
            //exit();
            //返回 文件流
            header("Content-type: " . $fileType); //类型
            header("Accept-Ranges: bytes");//告诉客户端浏览器返回的文件大小是按照字节进行计算的
            header("Accept-Length: " . $request->getContentLength());//文件大小
            header("Content-Length: " . $request->getContentLength());//文件大小
            header('Content-Disposition: attachment; filename="' . time() . '.' . $type . '"'); //文件名
            echo $request->getBody();
            exit ();
        }
        //echo( '内容: , '. $request -> getContentLength()  );
        //echo '
';
        //echo  '参数:';
        //echo ($request -> getParams());
        //echo '' ;
    }
}
//  测试
$test1 = new TestImage();
$test1->load();