[CodeIgniter] 多檔上傳圖片並縮圖

用 CodeIgniter 做多檔上傳圖片，並希望同時縮圖(一大一小)，並新增至資料表中。
在官方討論區參考了一些寫法 .. 有空再把它優化一下，先記著寫法。

View 的表單，除了 form 記得用 enctype="multipart/form-data" 外，檔案上傳的 code 可以這樣下：

                  <input type="file" name="userfile1" /><br />
                  <input type="file" name="userfile2" /><br />
                  <input type="file" name="userfile3" /><br />
                  <input type="file" name="userfile4" /><br />
                  <input type="file" name="userfile5" /><br />

下面這段依需求放置在 Controller 裡：

		$config['upload_path'] = './uploads/';
		$config['allowed_types'] = 'jpg|jpeg|gif|png';
		$config['overwrite'] = false;
                $config['encrypt_name'] = TRUE;

		$this->load->library('upload',$config);
		$this->upload->initialize($config);

                foreach($_FILES as $key => $value)
                {

                    if( !empty($value['name']))
                    {

                        if ( ! $this->upload->do_upload($key))
                        {

                                $data["error"] = $this->upload->display_errors();
                                $this->load->model('Photo_model');
                                $data["photo"] = $this->Photo_model->getPhotoList();
                                $this->template->write_view('content','photoAdd',$data);
                                $this->template->render();

                        } else {

                                $fInfo = $this->upload->data();

                                $this->_createThumbnail($fInfo['full_path'],FALSE,"",330,480);
                                $this->_createThumbnail($fInfo['full_path'],TRUE,"_tn",110,160);

                                $this->validation->set_error_delimiters('','<br />');
                                $rules['status'] = "required|integer|max_length[1]";
                                $this->validation->set_rules($rules);

                                $fields['status']   = "Status";
                                $this->validation->set_fields($fields);

                                if($this->validation->run() == FALSE)
                                {
                                        $this->photoAdd();
                                }
                                else
                                {
                                        $this->load->model('Photo_model');
                                        $this->Photo_model->savePhoto("add");
                                }

                        }
                    }

                }

裡面有用到一個縮圖 function：

        function _createThumbnail($fileName, $isThumb, $thumbMarker="", $width, $height) {
            //settings
            $config['image_library'] = 'gd2';
            $config['source_image'] = $fileName;
            $config['create_thumb'] = $isThumb;
            $config['maintain_ratio'] = TRUE;
            $config['master_dim'] = 'width';
            if(isset($thumbMarker) && $thumbMarker!=""){
            $config['thumb_marker'] = $thumbMarker;
            }
            $config['width'] = $width;
            $config['height'] = $height;

            $this->load->library('image_lib', $config);
            $this->image_lib->clear();
            $this->image_lib->initialize($config);
            if(!$this->image_lib->resize()) echo $this->image_lib->display_errors();
        }

對了 … 因為上傳送出之後也會將紀錄新增至資料表中，所以 Model 取得上傳處理過的檔名可以這樣做：

	$thumb_img     = substr($this->upload->file_name, 0, -4)."_tn".$this->upload->file_ext;
	$large_img     = substr($this->upload->file_name, 0, -4).$this->upload->file_ext;