截断字符，如果文章字数超过指定字符个数，用省列号代替

        /// <summary>
        /// 中文：截断字符，如果文章字数超过指定字符个数，只显示指定数其他用...代替
        /// </summary>
        /// <param name="article">文本</param>
        /// <param name="num">字符数</param>
        /// <returns>string</returns>
        public static string ContentCN(object article, int num)
        {
            string content = (string)article;
            System.Text.ASCIIEncoding en = new System.Text.ASCIIEncoding();
            byte[] b = en.GetBytes(content);
            int len = 0;
            for (int i = 0; i < b.Length; i++)
            {
                if (b[i] == 63)  //判断是否为汉字或全脚符号
                {
                    len++;
                }
                len++;
            }
            if (len > num)
                content = content.Substring(0, num / 2 - 1) + "...";

            return content;
        }