递归 无穷找子类的递归

///id要找的父类的id
///把找到的子类的id存放到idList中 
private void GetAllSonPlateId(Guid id, ref List<Guid> idList)
        {
            try
            {
                List<Guid> gets = _videoR.GetSonId(id);
                if (gets.Count > 0)
                {
                    foreach (Guid item in gets)
                    {
                        idList.Add(id);
                        GetAllSonPlateId(item, ref idList);
                    }
                }
                else
                {
                    idList.Add(id);
                }
            }
            catch (Exception)
            {
            }
        }

 /// <summary>
        /// 获得一个栏目的子栏目的idList
        /// </summary>
        /// <returns></returns>
        public List<Guid> GetSonId(Guid id)
        {
            List<Guid> idList = new List<Guid>();
            
            try
            {
                var list = from plate in _db.Plate
                           where plate.ParentID == id
                           select plate.ID;
                idList.AddRange(list.ToList<Guid>());
                return idList;
            }
            catch (Exception)
            {
                return idList;
            }
        }

第二个代码

  /// <summary>
    /// 词条的列表  有百科类型
    /// </summary>
    public class WordList
    {
        public string BaikeType { get; set; }
        public Guid BaikeTypeID { get; set; }
        public List<Word> List { get; set; }
    } 


/// <summary>
        /// 词条列表
        /// </summary>
        /// <returns></returns>
        [HttpPost]
        public ActionResult citiaolist(Guid? id)
        {
            if (id.HasValue)
            {
                List<BaiKeType> baikelist = new List<BaiKeType>();
                List<WordList> list = new List<WordList>();
                List<WordList> self = _baikeR.GetOneCitiaoList(id.Value);
                if (self != null)
                {
                    list = list.Concat(self).ToList();
                }
                GetBaikeTypeSon(id.Value, ref baikelist);
                foreach (BaiKeType item in baikelist)
                {
                    List<WordList> temp = _baikeR.GetOneCitiaoList(item.ID);
                    if (temp != null)
                    {
                        list = list.Concat(temp).ToList();
                    }
                }
                ViewData["list"] = list;
            }
            else
            {
                ViewData["list"] = _baikeR.GetCitiaoList();
            }
            return View();
        }
//找到这个类别的所有子类别，返回到list中
        private void GetBaikeTypeSon(Guid id, ref List<BaiKeType> list)
        {
            try
            {
                List<BaiKeType> baikelist = _baikeR.GetBaikeTypeListByParentID(id);
                if (baikelist != null && baikelist.Count > 0)
                {
                    list = list.Concat(baikelist).ToList();
                    foreach (BaiKeType item in baikelist)
                    {
                        GetBaikeTypeSon(item.ID, ref list);
                    }
                }
            }
            catch { }
        }