function email()
{
   $this->load->library('email');
   $config['protocol'] = 'smtp';
   $config['smtp_host'] = 'smtp.163.com';
   $config['smtp_user'] = 'jb51@163.com';//这里写上你的163邮箱账户
   $config['smtp_pass'] = 'jb51;';//这里写上你的163邮箱密码
   $config['mailtype'] = 'html';
   $config['validate'] = true;
   $config['priority'] = 1;
   $config['crlf'] = "\r\n";
   $config['smtp_port'] = 25;
   $config['charset'] = 'utf-8';
   $config['wordwrap'] = TRUE;
   $this->email->initialize($config);
   $this->email->from('jb51@163.com', '');//发件人
   $this->email->to('123456789@qq.com');
   $this->email->message('哈哈，测试邮件发送');
   $this->email->send();
   echo $this->email->print_debugger();
}