一直以为的Math.Round为四舍五入原来是四舍六入五留双

        /// <summary>
        /// 小数保留位数处理
        /// </summary>
        /// <param name="value">值</param>
        /// <param name="digitNum">保留位数</param>
        /// <returns></returns>
        public static decimal MathRound(decimal value, int digitNum)
        {
            return Math.Round(value, digitNum);
        }