protected void AddNewItemButton_Click(object sender, EventArgs e)
{
ListManager listManager = new ListManager();
string listId = Request.QueryString["UserListId"];
listManager.AddItemToList(int.Parse(listId), NewItemTitleTextBox.Text);
IEnumerable <Item> listItems = listManager.GetListItems(int.Parse(listId));
ListItemsRepeater.DataSource = listItems;
ListItemsRepeater.DataBind();
}
