/// <summary>
/// When the form is closing by user, update the url in database by passing the item in listBox and removeList.
/// The item in listBox might contain both existed and new added url
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void form_FormClosing(object sender, FormClosingEventArgs e)
{
List <string> existed = lb_RssUrlStore.Items.Cast <string>().ToList();
if (e.CloseReason == CloseReason.UserClosing)
{
RssFeedReader.updateUrlInDb(existed, removeList);
Action instance = actionMainForm;
if (instance != null)
{
instance();
}
}
}
