调取当前栏目父栏目自定义字段

int columnId = (int)ViewBag.ColumnId;//当前栏目id
     int siteId = (int)ViewBag.SiteId;//当前站点id
     IEnumerable<dynamic> ColumnList = Html.GetColumnList(c => c.Show == 1 && c.SiteId == siteId);
    dynamic topParentData = Html.GetTopParentData(ColumnList, columnId);//获取当前栏目的父级ids
    int parentId = topParentData.Id;
    string thumbnail = Html.GetColumnContentSet(parentId).Thumbnail;