输入数据统一入口类

@@##@@ http://blog.qita.in/?post=494

/**
 * 获取输入统一入口
 */
class cls_request
{
	private  $getdata;    //存储get的数据
	private  $postdata;   //存储post的数据
	private	 $requestdata; //存储request的数据
	private  $filedata;   //存储file数据
	private  $cookiedata; //存储cookie
	static 	 $_instance;  //本类的实例

	private function __construct()
	{
		$this->getdata    = self::format_data($_GET);
		$this->postdata   = self::format_data($_POST);
		$this->requestdata = array_merge($this->getdata, $this->postdata);
		$this->cookiedata = self::format_data($_COOKIE);
		$this->filedata = self::format_data($_FILES);
	}
	/**
	 * 类的初始化方法
	 *
	 * @return cls_request 对象
	 */
	public static function get_instance()
	{
		if(!(self::$_instance instanceof self))
		{
			self::$_instance = new self();
		}
		return self::$_instance;
	}

	/**
	 * 获取GET传递过来的数值变量
	 *
	 * @param string $key
	 * @return int or big int
	 */
	public	function get_num($key)
	{
		if(!isset($this->getdata[$key]))
		{
			return false;
		}
		return $this->to_num($this->getdata[$key]);
	}

	/**
	 * 获取POST传递过来的数值变量
	 *
	 * @param string $key
	 * @return int or big int
	 */
	public	function post_num($key)
	{
		if(!isset($this->postdata[$key]))
		{
			return false;
		}
		return $this->to_num($this->postdata[$key]);
	}

	/**
	 * 获取REQUEST传递过来的数值变量
	 *
	 * @param string $key
	 * @return int or big int
	 */
	public function request_num($key)
	{
		if(!isset($this->requestdata[$key]))
		{
			return false;
		}
		return $this->to_num($this->requestdata[$key]);
	}

	/**
	 * 获取Cookie传递过来的数值变量
	 *
	 * @param string $key
	 * @return int or big int
	 */
	public function cookie_num($key)
	{
		if(!isset($this->cookiedata[$key]))
		{
			return false;
		}
		return $this->to_num($this->cookiedata[$key]);
	}

	/**
	 * 获取Files传递过来的变量值
	 *
	 * @param string $key
	 * @return array
	 */
	public function file_data($key)
	{
		return $this->filedata[$key];
	}

	/**
	 * 获取GET传递过来的字符串变量
	 *
	 * @param string $key
	 * @param boolen $isfilter 是否过滤
	 * @return string
	 */
	public	function get_string($key,$isfilter=true)
	{
		if(!isset($this->getdata[$key]))
		{
			return false;
		}
		if($isfilter)
		{
			return $this->filter_string($this->getdata[$key]);
		}
		else
		{
			return $this->getdata[$key];
		}
	}

	/**
	 * 获取POST传递过来的字符串变量
	 *
	 * @param string $key
	 * @param boolen $isfilter 是否过滤
	 * @return string
	 */
	public	function post_string($key,$isfilter=true)
	{
		if(!isset($this->postdata[$key]))
		{
			return false;
		}
		if($isfilter)
		{
			return $this->filter_string($this->postdata[$key]);
		}
		else
		{
			return $this->postdata[$key];
		}
	}

	/**
	 * 获取REQUEST传递过来的字符串变量
	 *
	 * @param string $key
	 * @param boolen $isfilter 是否过滤
	 * @return string
	 */
	public	function request_string($key,$isfilter=true)
	{
		if(!isset($this->requestdata[$key]))
		{
			return false;
		}
		if($isfilter)
		{
			return $this->filter_string($this->requestdata[$key]);
		}
		else
		{
			return $this->requestdata[$key];
		}
	}

	/**
	 * 获取COOKIE传递过来的字符串变量
	 *
	 * @param string $key
	 * @param boolen $isfilter 是否过滤
	 * @return string
	 */
	public function cookie_string($key,$isfilter=true)
	{
		if(!isset($this->cookiedata[$key]))
		{
			return false;
		}
		if($isfilter)
		{
			return $this->filter_string($this->cookiedata[$key]);
		}
		else
		{
			return $this->cookiedata[$key];
		}
	}

	/**
	 * 格式化数据,将数据转存
	 *
	 * @param array $data
	 */
	private	function format_data($data)
	{
		$result = array();
        if(!is_array($data))
        {
            $data = array();
        }
		while(list($key, $value) = each($data))
		{
			//处理checkbox之类的数据
		    if(is_array($value))
		    {
		         $result[$key]=$value;
		    }
		    else //普通数据
		    {
		    	$result[$key] = trim($value);
		    }
		}
		return $result;
	}
	/**
	 * 转换为数字
	 *
	 * @param string $num
	 * @return int or big int or false
	 */
	private function to_num($num)
	{
		if(is_numeric($num))
		{
			return intval($num);
		}
		else
		{
			return false;
		}
	}
	/**
	 * 转换过滤字符串
	 *
	 * @param string/array $data
	 * @return string
	 */
	private function filter_string($data)
	{
		if($data===NULL)
		{
			return false;
		}
		if (is_array($data))
		{
			foreach ($data as $k=>$v)
			{
			    $data[$k] = htmlspecialchars($v, ENT_QUOTES);
			}
			return $data;
		}
		else
		{
			return htmlspecialchars($data, ENT_QUOTES);
		}
	}
}