表示一天中的某个时间点的 Time 结构

    /// <summary>
    /// Time 结构表示一天中的某个时间点，精确到秒。与 DateTime 不同，Time 结构不包含日期部分。
    /// </summary>
    [Serializable]
    public struct Time : ISerializable, IXmlSerializable
    {
        private int _hour;
        private int _minute;
        private int _second;

        /// <summary>
        /// 从 TimeSpan 构造 Time，例如，使用 DateTime.TimeOfDay 作为实参。
        /// </summary>
        /// <param name="timeSpan"></param>
        public Time(TimeSpan timeSpan)
            : this(timeSpan.Hours, timeSpan.Minutes, timeSpan.Minutes)
        {
            
        }

        /// <summary>
        /// 构造 Time 的新实例。秒部分为 0。
        /// </summary>
        /// <param name="hour">小时部分，0 - 23</param>
        /// <param name="minute">分钟部分，0 - 59</param>
        public Time(int hour, int minute)
            : this(hour, minute, 0)
        {

        }

        /// <summary>
        /// 构造 Time 的新实例。
        /// </summary>
        /// <param name="hour">小时部分，0 - 23</param>
        /// <param name="minute">分钟部分，0 - 59</param>
        /// <param name="second">秒部分，0 - 59</param>
        public Time(int hour, int minute, int second)
        {
            if (hour < 0 || hour > 23)
            {
                throw new ArgumentOutOfRangeException("hour");
            }
            if (minute < 0 || minute > 59)
            {
                throw new ArgumentOutOfRangeException("minute");
            }
            if (second < 0 || minute > 59)
            {
                throw new ArgumentOutOfRangeException("second");
            }

            _hour = hour;
            _minute = minute;
            _second = second;
        }

        public Time(SerializationInfo info, StreamingContext context)
        {
            _hour = info.GetInt32("Hour");
            _minute = info.GetInt32("Minute");
            _second = info.GetInt32("Second");
        }

        /// <summary>
        /// 小时部分
        /// </summary>
        public int Hour
        {
            get
            {
                return _hour;
            }
        }

        /// <summary>
        /// 分钟部分
        /// </summary>
        public int Minute
        {
            get
            {
                return _minute;
            }
        }

        /// <summary>
        /// 秒部分
        /// </summary>
        public int Second
        {
            get
            {
                return _second;
            }
        }

        public override bool Equals(object obj)
        {
            if (obj == null || obj.GetType() != typeof(Time))
            {
                return false;
            }
            Time other = (Time)obj;
            return _hour == other._hour
                && _minute == other._minute
                && _second == other._second;
        }

        public override int GetHashCode()
        {
            return _hour.GetHashCode()
                ^ _minute.GetHashCode()
                ^ _second.GetHashCode();
        }

        public static bool operator==(Time a, Time b)
        {
            return a._hour == b._hour
                && a._minute == b._minute
                && a._second == b._second;
        }

        public static bool operator !=(Time a, Time b)
        {
            return !(a == b);
        }

        /// <summary>
        /// 将此实例转换成 TimeSpan
        /// </summary>
        /// <returns></returns>
        public TimeSpan ToTimeSpan()
        {
            return new TimeSpan(_hour, _minute, _second);
        }

        #region ISerializable 成员

        public void GetObjectData(SerializationInfo info, StreamingContext context)
        {
            info.AddValue("hour", _hour);
            info.AddValue("minute", _minute);
            info.AddValue("second", _second);
        }

        #endregion

        #region IXmlSerializable 成员

        public System.Xml.Schema.XmlSchema GetSchema()
        {
            return null;
        }

        public void ReadXml(System.Xml.XmlReader reader)
        {
            _hour = Convert.ToInt32(reader.GetAttribute("hour"));
            _minute = Convert.ToInt32(reader.GetAttribute("minute"));
            _second = Convert.ToInt32(reader.GetAttribute("second"));
            reader.Read();
        }

        public void WriteXml(System.Xml.XmlWriter writer)
        {
            writer.WriteAttributeString("hour", _hour.ToString());
            writer.WriteAttributeString("minute", _minute.ToString());
            writer.WriteAttributeString("second", _second.ToString());
        }

        #endregion
    }