public static void AddItems <TItem>(this ListBox listBox, TItem[] items, bool clearItemsBeforeAdd = true, bool throwIfNull = false) { if (clearItemsBeforeAdd) { listBox.ClearItemsIfExist(); } if (items == null) { if (throwIfNull) { throw new ArgumentNullException(ReflectionUtils.GetNameOf(() => items), "Nie przekazano elementów do dodania."); } else { return; } } items.ForEach(x => listBox.Items.Add(x)); }