//点击添加其他文件(pdf,ppt,word)
        private void addDocument_Click(object sender, EventArgs e)
        {
            OpenFileDialog od1 = new OpenFileDialog();

            od1.InitialDirectory = "c:\\";
            od1.Filter           = GetFile.DocumentFilter;
            od1.FilterIndex      = 2;
            od1.RestoreDirectory = true;

            if (od1.ShowDialog() == DialogResult.OK)
            {
                Path = od1.FileName;
                MessageBox.Show("已选择文件:" + Path, "选择文件提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }

            service.AddDocument(Path, ListID);
            videos = service.GetFileFromList(ListID);
            ListViewUpdate(videos);
            ListViewUpdate(ListID);
            listBox1.SelectedIndex = 0;
        }