1、初始化对象：\Magento\Framework\Filesystem\Io\Ftp

   protected $ftp;   public function __construct(       \Magento\Framework\Filesystem\Io\Ftp $ftp   ){       $this->ftp = $ftp;   }

2、Build the FTP Connect

    $open = $this->ftp->open(         array(            'host' => ‘test.localhost.com’,            'user' => ‘test’,            'password' => ‘test’,            'ssl' => '',//true            'passive' => ''//true                         )    );

Use the written function to upload a file to the server

    if ($open) {        //方式一：直接读一个文件上传        $fileName = ‘test.csv’;        $content = file_get_contents(DirectoryList::VAR_DIR . '/' . $fileName);        $this->ftp->write(self::FILE_NAME_ON_FTP, $content);        $this->ftp->close();        //方式二：创建文件并一行行写        $fileName = 'test.csv';        $content = "姓名,年龄,班级\n张三,18,大一";        $result = $this->ftp->write($fileName, $content);        $this->ftp->close();    }