private static string RecursionMenuTree(List<Menu> menus, long parentID = 0, StringBuilder sb = null) { if (sb == null) { sb = new StringBuilder(); } var parentMenus = menus.Where(x => x.ParentID == parentID).ToList(); parentMenus.ForEach(x => { sb.Append("{"); sb.AppendFormat(""ID":"{0}",", x.ID.ToString()); sb.AppendFormat(""Path":"{0}",", x.Path); sb.AppendFormat(""MenuName":"{0}",", x.MenuName); sb.AppendFormat(""OrderNum":"{0}",", x.OrderNum.ToString()); sb.AppendFormat(""Type":"{0}"", x.Type.ToString()); var children = menus.Where(c => c.ParentID == x.ID); if (children?.Count() > 0) { sb.Append(""children":["); RecursionMenuTree(menus, x.ID, sb); sb.Append("]"); } sb.Append("},"); }); return sb.ToString(); }