Cross-site request forgery (CSRF) $_GET

[eluser]behnampmdg3[/eluser]
Hello;

How can I make it so only visitors from this website can call this function (and delete the photos)?

Thanks

Code:

public function delete($photo)
  {
   $this->load->model('load_photos_model');
   $delete = $this->load_photos_model->delete($photo);
   if($delete)
    {
     unlink('uploads/'.$photo.'.jpg');
     redirect(site_url()."gallery");
    }
   else
    {
     redirect(site_url()."gallery");
    }
  }