Input data unified entry class

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

/**
 * Get the unified entrance for input
*/
class cls_request
{
 private $getdata; //Storage get data
 private $postdata; //Storage post data
 private $requestdata; //Storage request data
 private $filedata; //Storage file data
 private $cookiedata; //Storage cookie
 static $_instance; //Instance of this class

 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);
 }
 /**
 * Class initialization method
 *
 * @return cls_request object
*/
 public static function get_instance()
 {
 if(!(self::$_instance instanceof self))
 {
 self::$_instance = new self();
 }
 return self::$_instance;
 }

 /**
 * Get the numerical variable passed by GET
 *
 * @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]);
 }

 /**
 * Get the numerical variable passed by POST
 *
 * @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]);
 }

 /**
 * Get the numerical variable passed by REQUEST
 *
 * @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]);
 }

 /**
 * Get the numerical variable passed by Cookie
 *
 * @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]);
 }

 /**
 * Get the variable value passed by Files
 *
 * @param string $key
 * @return array
*/
 public function file_data($key)
 {
 return $this->filedata[$key] ;
 }

 /**
 * Get the string variable passed by GET
 *
 * @param string $key
 * @param boolen $isfilter whether to filter
 * @return string
*/
 public function get_string($key,$isfilter=true)
 {
 if(!isset($this->getdata[$key]))
 {
 return false;
 }
 if($isfilter)
 {
 return $this->filter_string($this->getdata[$key]);
 }
 else
 {
 return $this->getdata[$key ];
 }
 }

 /**
 * Get the string variable passed by POST
 *
 * @param string $key
 * @param boolen $isfilter whether to filter
 * @return string
*/
 public function post_string($key,$isfilter=true)
 {
 if(!isset($this->postdata[$key]))
 {
 return false;
 }
 if($isfilter)
 {
 return $this->filter_string($this->postdata[$key]);
 }
 else
 {
 return $this->postdata [$key];
 }
 }

 /**
 * Get the string variable passed by REQUEST
 *
 * @param string $key
 * @param boolen $isfilter whether to filter
 * @return string
*/
 public function request_string($key,$isfilter=true)
 {
 if(!isset($this->requestdata[$key] ))
 {
 return false;
 }
 if($isfilter)
 {
 return $this->filter_string($this->requestdata[$key]);
 }
 else
 {
 return $this- >requestdata[$key];
 }
 }

 /**
 * Get the string variable passed by COOKIE
 *
 * @param string $key
 * @param boolen $isfilter whether to filter
 * @return string
*/
 public function cookie_string($key,$isfilter=true)
 {
 if(!isset($this->cookiedata[ $key]))
 {
 return false;
 }
 if($isfilter)
 {
 return $this->filter_string($this->cookiedata[$key]);
 }
 else
 {
 return $this->cookiedata[$key];
 }
 }

	/**
 * Format data and transfer data
 *
 * @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;
	}
	/**
 * Convert to number
 *
 * @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;
		}
	}
	/**
 * Convert filter string
 *
 * @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);
		}
	}
}