/// <summary>
        /// 如果是删除 目录 ,查找该目录的所有子目录,查找所有的文件
        /// 若是删除文档,则直接删除
        /// </summary>
        /// <returns></returns>
        public List <DBItem> FindTarget(string dbName, string collectionName, string id)
        {
            List <DBItem> list = new List <DBItem>();
            var           db   = DataStorage.GetInstance(DBType.MongoDB);

            if (collectionName == CONST.DB.CollectionName_CategoryItem)
            {
                var categoryList = CategoryManager.GetInstance().GetSubCategory(id);
                categoryList.Add(CategoryItem.Load(id));
                foreach (var category in categoryList)
                {
                    var dbItem1 = DBItem.Create(CONST.DB.DBName_DocService, CONST.DB.CollectionName_CategoryItem, category.id);
                    list.Add(dbItem1);
                    var docList = DocManager.GetInstance().Find("{'CategoryID':'" + dbItem1.ID + "'}", "{}", "{}", 0, int.MaxValue);
                    foreach (var doc in docList)
                    {
                        var dbItem2 = DBItem.Create(CONST.DB.DBName_DocService, CONST.DB.CollectionName_DocItem, doc.ID);
                        list.Add(dbItem2);
                    }
                }
            }
            else
            {
                list.Add(DBItem.Create(dbName, collectionName, id));
            }
            return(list);
        }