C# DateTime.IsDaylightSavingTime方法代码示例

 public static int getSeason(DateTime date)
 {
     int summer=date.IsDaylightSavingTime() ? 1 : 0;
     int season=date.Year * 2;
     if (date.IsDaylightSavingTime()) {
         season++;
     } else if (date.Month>6) {
         season += 2;
     }
     return season;
 }

        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value == null)
            {
                return null;
            }

            Version v = value as Version;

            if (v == null)
            {
                throw new ArgumentException("Input value must be a Version object (it is a " + value.GetType().FullName + ")", "value");
            }

            if (v.Build != 0)
            {
                var time = new DateTime(2000, 1, 1).AddDays(v.Build).AddSeconds(v.Revision * 2);
                if (time.IsDaylightSavingTime())
                    time = time.AddHours(1);
                return time;
            }
            else
            {
                return null;
            }
        }

 public static string ToShortDateTime(DateTime date, bool twoLines)
 {
     var sb = new StringBuilder();
     sb.Append(date.ToShortDateString());
     sb.Append(twoLines ? "<br />" : " ");
     sb.Append(date.ToShortTimeString());
     sb.Append(date.IsDaylightSavingTime() ? " (pdt)" : " (pst)");
     return sb.ToString();
 }

        public void UtcToUserTimeZoneShouldWork()
        {
            var utcDateTime = new DateTime(2014, 6, 1, 12, 0, 0, DateTimeKind.Utc);

            Assert.IsFalse(utcDateTime.IsDaylightSavingTime());
            var dateTime = Utils.UtcToUserTimeZone(utcDateTime, "GMT Standard Time");

            Assert.IsTrue(Utils.IsGmtDaylightSavingTime(dateTime, "GMT Standard Time"));
        }

        public DateFunctionality()
        {
            DateTime dt = new DateTime(2004, 10, 17);
             Console.WriteLine("The day of {0} is {1}", dt.Date, dt.DayOfWeek);
             dt = dt.AddMonths(2);
             Console.WriteLine("Daylight savings: {0}", dt.IsDaylightSavingTime());

             TimeSpan timeSpan = new TimeSpan(4, 30, 0);
             Console.WriteLine(timeSpan);
             Console.WriteLine(timeSpan.Subtract(new TimeSpan(0,15,0)));
        }

        /// <summary>
        /// Aligns a date/time with the User's preferences (if any).
        /// </summary>
        /// <param name="dateTime">The date/time to align.</param>
        /// <returns>The aligned date/time.</returns>
        public static DateTime AlignWithTimezone(DateTime dateTime)
        {
            // First, look for hard-stored user's preferences
            // If they are not available, look at the cookie

            int? tempShift = LoadTimezoneFromUserData();
            if(!tempShift.HasValue) tempShift = LoadTimezoneFromCookie();

            int shift = tempShift.HasValue ? tempShift.Value : Settings.DefaultTimezone;
            return dateTime.ToUniversalTime().AddMinutes(shift + (dateTime.IsDaylightSavingTime() ? 60 : 0));
        }

        public void Print()
        {
            System.Int32 i = new System.Int32();
            i = 23;
            Console.WriteLine(i.GetHashCode());
            Console.WriteLine(i.GetType());
            Console.WriteLine(i.GetTypeCode());
            Console.WriteLine(i.ToString());
            if (i.CompareTo(20) < 0)
                Console.WriteLine("{0} < 20", i);
            else if (i.CompareTo(20) == 0)
                Console.WriteLine("i equals 20");
            else
                Console.WriteLine("i > 20");
            Console.WriteLine(System.Int32.MinValue);
            Console.WriteLine(System.Int32.MaxValue);
            Console.WriteLine(System.Double.Epsilon);
            Console.WriteLine(System.Double.PositiveInfinity);
            Console.WriteLine(System.Double.NegativeInfinity);
            Console.WriteLine(System.Boolean.FalseString);
            Console.WriteLine(System.Boolean.TrueString);

            Console.WriteLine(System.Char.IsDigit('1'));
            Console.WriteLine(System.Char.IsLetter('9'));
            Console.WriteLine(System.Char.IsWhiteSpace("naynish chaughule", 7));
            Console.WriteLine(System.Char.IsPunctuation('?'));

            //parsing
            double d = System.Double.Parse("90.35");
            Console.WriteLine(d);
            System.Int64 longVar = Convert.ToInt64("43654703826562");
            Console.WriteLine(longVar);

            Console.WriteLine(System.Guid.NewGuid());
            System.DateTime dt = new DateTime(2012, 6, 04);
            Console.WriteLine(dt.ToLongDateString());
            Console.WriteLine(DateTime.Now.ToLongTimeString());
            Console.WriteLine(dt.DayOfWeek);
            Console.WriteLine(dt.AddMonths(5).ToLongDateString());
            Console.WriteLine("{0} {1} {2}", dt.Date, dt.DayOfYear, dt.IsDaylightSavingTime());

            TimeSpan ts = new TimeSpan(24, 30, 30);
            Console.WriteLine(dt.Add(ts).ToLongDateString());
            Console.WriteLine(ts.Subtract(new TimeSpan(2,30, 45)));
            NumericsDemo();
            WorkingWithStrings();
        }

		public DateTime_type ()
		{
			// This constructor takes (year, month, day). 
			DateTime dt = new DateTime( 2015, 10, 17);

			// What day of the month is this? 
			Console.WriteLine(" The day of {0} is {1}", dt.Date, dt.DayOfWeek);

			// Month is now December. 
			dt = dt.AddMonths( 2); Console.WriteLine(" Daylight savings: {0}", dt.IsDaylightSavingTime());

			// This constructor takes (hours, minutes, seconds). 
			TimeSpan ts = new TimeSpan( 4, 30, 0); 
			Console.WriteLine( ts);

			// Subtract 15 minutes from the current TimeSpan and
			Console.WriteLine( ts.Subtract( new TimeSpan( 0, 15, 0)));

		}

        public void GetXsdtDateRepresentationForTest()
        {
            XsdtTypeConverter target = new XsdtTypeConverter();

            DateTime d = new DateTime(2007, 10, 17, 19, 42, 01); // TODO: Initialize to an appropriate value

            XsdtPrimitiveDataType dt = XsdtPrimitiveDataType.XsdtDateTime; // TODO: Initialize to an appropriate value

            XsdtAttribute attr = new XsdtAttribute(true, "dateTime"); // TODO: Initialize to an appropriate value

            string expected = "2007-10-17T19:42:01+" + ((d.IsDaylightSavingTime())?"11:00":"10:00");
            string actual;
            XsdtTypeConverter tc = new XsdtTypeConverter();
            actual = tc.GetXsdtDateRepresentationFor(d, dt, attr);

            Assert.AreEqual(expected, actual,
                            "LinqToRdf.XsdtTypeConverter.GetXsdtDateRepresentationFor did not return the expec" +
                            "ted value.");
        }

        /// <summary>
        /// Returns the versions build and revision components as a
        /// <see cref="DateTime"/>.
        /// </summary>
        /// <remarks>
        /// Note that this will only work correctly if the version was built
        /// with the automatic version number feature turned on (eg Maj.Min.*).
        /// </remarks>
        /// <param name="version">Version to get the DateTime for.</param>
        /// <returns>DateTime object for the build/revision.</returns>
        public static DateTime? GetBuildRevisionAsDateTime(Version version) {
            if (version == null) {
                return null;
            }
            DateTime dt = new DateTime(2000, 1, 1, 0, 0, 0);

            // If the start of the year is DLS but isn't now or vice versa then
            // we need to either add or subtract an hour.
            if (DateTime.Now.IsDaylightSavingTime() != dt.IsDaylightSavingTime()) {
                if (DateTime.Now.IsDaylightSavingTime()) {
                    dt = dt.AddHours(1);
                } else {
                    dt = dt.AddHours(-1);
                }
            }

            dt = dt.AddDays(version.Build);
            dt = dt.AddSeconds(version.Revision * 2);
            return dt;
        }

        public IeTime56(long timestamp, TimeZone timeZone, bool invalid)
        {
            var datetime = new DateTime(timestamp);
            var ms = datetime.Millisecond + 1000*datetime.Second;

            value[0] = (byte) ms;
            value[1] = (byte) (ms >> 8);
            value[2] = (byte) datetime.Minute;

            if (invalid)
            {
                value[2] |= 0x80;
            }
            value[3] = (byte) datetime.Hour;
            if (datetime.IsDaylightSavingTime())
            {
                value[3] |= 0x80;
            }
            value[4] = (byte) (datetime.Day + ((((int) datetime.DayOfWeek + 5)%7 + 1) << 5));
            value[5] = (byte) (datetime.Month + 1);
            value[6] = (byte) (datetime.Year%100);
        }

        static void Main(string[] args)
        {
            Console.WriteLine("=> Dates and Times");

            // Этот конструктор принимает год, месяц и день
            DateTime dt = new DateTime(2014, 10, 20);

            // Какой это день месяца
            Console.WriteLine("The day of {0} is {1}", dt.Date, dt.DayOfWeek);

            // Сейчас месяц декабрь
            dt = dt.AddMonths(1);
            Console.WriteLine("Daylight savings: {0}", dt.IsDaylightSavingTime());

            // Этот конструктор принимает часы, минуты и секунды
            TimeSpan ts = new TimeSpan(8, 42, 30);

            Console.WriteLine(ts);

            // Вычесть 15 минут из текущего TimeSpan и вывести результат
            Console.WriteLine(ts.Subtract(new TimeSpan(0, 15, 0)));
            Console.ReadLine();
        }

 /// <summary>
 /// Aligns a date/time with the default timezone.
 /// </summary>
 /// <param name="dateTime">The date/time to align.</param>
 /// <returns>The aligned date/time.</returns>
 public static DateTime AlignWithServerTimezone(DateTime dateTime)
 {
     return dateTime.ToUniversalTime().AddMinutes(Settings.DefaultTimezone + (dateTime.IsDaylightSavingTime() ? 60 : 0));
 }

        public static void Today()
        {
            DateTime today = DateTime.Today;
            DateTime now = DateTime.Now;
            VerifyDateTime(today, now.Year, now.Month, now.Day, 0, 0, 0, 0, DateTimeKind.Local);

            today = new DateTime(now.Year, now.Month, now.Day, now.Hour, now.Minute, now.Second, DateTimeKind.Utc);
            Assert.Equal(DateTimeKind.Utc, today.Kind);
            Assert.False(today.IsDaylightSavingTime());
        }

        private DateTime AdjustTime_Win32ToDotNet(DateTime time)
        {
            // If I read a time from a file with GetLastWriteTime() (etc), I need
            // to adjust it for display in the .NET environment.
            if (time.Kind == DateTimeKind.Utc) return time;
            DateTime adjusted = time;
            if (DateTime.Now.IsDaylightSavingTime() && !time.IsDaylightSavingTime())
                adjusted = time + new System.TimeSpan(1, 0, 0);

            else if (!DateTime.Now.IsDaylightSavingTime() && time.IsDaylightSavingTime())
                adjusted = time - new System.TimeSpan(1, 0, 0);

            return adjusted;
        }