public?function?captcha()
	{
		$this->load->helper('url');
		$this->load->helper('captcha');

		$vals?=?array(
			'img_path'?=>?'./captcha/',
			'img_url'?=>?base_url().'/captcha/',
			'img_width'?=>'100',
			'img_height'?=>'30',
			'expiration'?=>?'10',
		);
		$cap?=?create_captcha($vals);
		echo?$cap['image'];
	}

必須創(chuàng)建 文件夾