php 입력 데이터 통합 클래스 인 스 턴 스

<?php
class cls_request{
 private $getdata;//  get   
 private $postdata;//  post   
 private $requestdata;//  request   
 private $filedata;//  file   
 private $cookiedata;//  cooki
 static $_instance;//     
 
 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);
 }
 //     ，  cls_request  
 public static function get_instance(){
 if(!(self::$_instance instanceof self)){
  self::$_instance = new self();
 }
 return self::$_instance;
 }
 //  GET         
 public function get_num($key){
 if(!isset($this->getdata[$key])){
  return false;
 }
 return $this->to_num($this->getdata[$key]);
 }
 //  POST         
 public function post_num($key){
 if(!isset($this->postdata[$key])){
  return false;
 }
 return $this->to_num($this->postdata[$key]);
 }
 //  Request         
 public function request_num($key){
 if(!isset($this->requestdata[$key])){
  return false;
 }
 return $this->to_num($this->requestdata[$key]);
 }
 //  Cookie         
 public function cookie_num($key){
 if(!isset($this->cookiedata[$key])){
  return false;
 }
 return $this->to_num($this->cookiedata[$key]);
 }
 //  File         
 public function filedata($key){
 return $this->filedata[$key];//    
 }
 //  GET          
 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];
 }
 }
 //  POST          
 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];
 }
 }
 //  Request          
 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];
 }
 }
 //  Cookie          
 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];
 }
 }
 //     
 private function format_data($data){
 $result = array();
 if(!is_array($data)){
  $data = array();
 }
 /*
 *list()             。          ，
 *   0   ，     
 *each()
 */
 while(list($key,$value) = each($data)){//    
  //  checkbox     
  if(is_array($value)){
  $result[$key]=$value;
  }else{//    
  $result[$key] = trim($value);
  //                 
  }
 }
 }
 //    
 private function to_num($num){
 if(is_numeric($num)){
  return intval($num);//       
 }else{
  return false;
 }
 }
 //       
 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);
  //           html  
  }
  return $data;
 }else{//     
  return htmlspecialchars($data,ENT_QUOTES);
 }
 }
}
?>