How to upload image file

[eluser]sherpa[/eluser]
use callback function in the rules

Code:

$this->form_validation->set_rules('fashion_thumbnail_id',"Thumbnail Image",'callback__thumbnail_check');


    function _thumbnail_check($str){
        if($_FILES['fashion_thumbnail_id']['error'] == 4){
            $this->form_validation->set_message('_thumbnail_check','The %s image should be provided.');
            return FALSE;
        }
        else{
                return TRUE;
        }
    }