//Ö´ÐÐɾ³ý
        public void activeDelete()
        {
            if (showItemList == null)
            {
                return;
            }
            ArrayList arrayList = new ArrayList();

            foreach (int index in listBox_content.SelectedIndices)
            {
                arrayList.Add(index);
            }
            while (arrayList.Count > 0)
            {
                int index = (int)arrayList[arrayList.Count - 1];
                arrayList.RemoveAt(arrayList.Count - 1);
                showItemList.removeElement(index);
            }
        }