function do_upload()
{
        //Betöltjük a Model-t ami az insertet fogja végezni
        $this->load->model('web/Profile_Model');

        //A tallózás mező neve a DOM-ban
        $fileName = 'browse_dom_element_name';
       
        //Feltöltés beállíások
        $config['upload_path'] = './cvdocstore/';
        $config['remove_spaces'] = true;
        $config['allowed_types'] = 'gif|jpg|png|doc|pdf|xls|docx|xlsx|tif';
       
        $insertData = array();
        $insertData['id'] = $this->input->xss_clean($this->input->post('upl_doctype_id'));
        $insertData['document_name'] = $this->input->xss_clean($this->input->post('upl_doctype_name'));
        $insertData['orig_file_name'] = $_FILES[$fileName]['name'];
        $insertData['file_size'] = $_FILES[$fileName]['size'];
        $insertData['upload_time'] = date('Y.m.d H:i:s');
 
        if($this->input->post('id') and isset($_FILES[$fileName]['name'])) {
   
          $this->load->library('upload', $config);
          if ( ! $this->upload->do_upload($fileName))
          {
              $ret= array('error' => $this->upload->display_errors());
              $ret['result'] = 0;
          }   
          else
          {
                $documentId = $this->Profile_Model->insertDocument($insertData);

              $ret= array('upload_data' => $this->upload->data());
              if($documentId) {
                $ret['result'] = 1;
              }
          }
        }
        return $ret;
}

CodeIgniter framework-ös file feltöltés. A CI upload library-jét használva. A kód természetesen csak részlet, viszont az alapelv jól látszik rajta.