/// <summary>
        /// 将扩展值集合组合为字符串
        /// </summary>
        /// <param name="extpropertycollection"></param>
        /// <returns></returns>
        protected string CombineExtProperty(NameValueCollection extpropertycollection, string modelname)
        {
            string                 str       = "";
            UD_ModelFieldsDAL      dal       = new UD_ModelFieldsDAL();
            IList <UD_ModelFields> extfields = dal.GetExtFieldsList(modelname);

            if (extpropertycollection != null)
            {
                foreach (UD_ModelFields modelfield in extfields)
                {
                    str += extpropertycollection[modelfield.FieldName] + "|";
                }
            }

            return(str);
        }
        /// <summary>
        /// 分解扩展属性值至集合
        /// </summary>
        /// <param name="tablename"></param>
        /// <param name="extfieldvalue"></param>
        /// <returns></returns>
        protected NameValueCollection SpiltExtProperty(string modelname, string extvalue)
        {
            NameValueCollection ExtPropertyCollection = new NameValueCollection();

            UD_ModelFieldsDAL      dal       = new UD_ModelFieldsDAL();
            IList <UD_ModelFields> extfields = dal.GetExtFieldsList(modelname);

            string[] vaules = extvalue.Split('|');

            for (int i = 0; i < extfields.Count; i++)
            {
                if (i < vaules.Length)
                {
                    ExtPropertyCollection.Add(extfields[i].FieldName, vaules[i]);
                }
                else
                {
                    ExtPropertyCollection.Add(extfields[i].FieldName, "");
                }
            }

            return(ExtPropertyCollection);
        }