여기서 이미지가 아닌파일을 방어하려면 어디다 어떤 구문을 주어야하나요..


<?


$savedir ="./files";
$temp = $pic_name;
$exist = file_exists("$savedir/$pic_name");

## file 존재여부 확인
           if($exist) {
                         echo("
                                <script>
                                        window.alert('이미 같은 이름의 파일이 존재합니다.')
                                        history.go(-1)
                                </script>");        
              exit;
           }

## 이상 없을시에 저장한다.
                
                                $file_ex = explode(".", $pic_name);
                                $extension = $file_ex[sizeof($file_ex) -1];

                                  if(strcmp($extension, "gif") ||
                                        strcmp($extension, "jpeg") ||                                        
                                        strcmp($extension, "jpg") ||        
                                        strcmp($extension, "bmp") ||                                        
                                        strcmp($extension, "png") ||                                        
                                        strcmp($extension, "jpe")                                         
                                                                                 
                                        )
                                                {
                                                
                        $s_userfile = $pic_name;

                        if(!copy($pic, "$savedir/$s_userfile")) {
                                echo("
                                                        <script>
                                                                alert('파일을 디렉토리에 업로드하는데 실패했습니다. \n\n관리자에게 문의해주세요.')
                                                                history.go(-1)
                                                        </script>
                                                        ");
                                                        exit;
                        }
                        unlink($pic);
                                                }else

                                {echo("
                                                        <script>
                                                                alert('죄송합니다. 선택한 파일은 자료실에 등록할수 없는 확장자입니다. \n\n이미지화일만 올려주셔여..')
                                                                history.go(-1)
                                                        </script>
                                                        ");
                                                        exit;
                                                        }
                                                        




?>