c# - DDay Ical 库是否正确计算重复规则？

Question

我已经进行了一些测试。这是我的代码:

var systemTimeZone = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time");
var icalTimeZone = iCalTimeZone.FromSystemTimeZone(systemTimeZone);

var startTimeSearch = new DateTime(2015, 9, 8, 0, 0, 0, DateTimeKind.Utc);
var endTimeSearch = new DateTime(2015, 12, 1, 00, 0, 0, DateTimeKind.Utc);

var iCalendar = new iCalendar();
var pacificTimeZone = _iCalendar.AddTimeZone(icalTimeZone);

var event = new Event
{
    Summary = "This is an event at 2015-09-08 10:30 PST (2015-09-08 17:30 UTC)",
    DTStart = new iCalDateTime(2015, 9, 8, 10, 30, 0, pacificTimeZone.TZID, iCalendar),
    Duration = new TimeSpan(0, 1, 0, 0)
};

var rp = new RecurrencePattern("FREQ=WEEKLY;UNTIL=20151112T080000Z;WKST=SU;BYDAY=TU");

event.RecurrenceRules.Add(rp);
iCalendar.Events.Add(_event);
var occurrences = iCalendar.GetOccurrences(startTimeSearch, endTimeSearch);

---

结果如下:

出现 10 次 - 这是出现的 Period.StartTime.Value 和 UTC 属性

值 - 9/8/2015 10:30:00 - UTC 9/8/2015 17:30:00
值 - 9/15/2015 10:30:00 - UTC 9/15/2015 17:30:00
值 - 9/22/2015 10:30:00 - UTC 9/22/2015 17:30:00
值 - 9/29/2015 10:30:00 - UTC 9/29/2015 17:30:00
值 - 10/6/2015 10:30:00 - UTC 10/6/2015 17:30:00
值 - 10/13/2015 10:30:00 - UTC 10/13/2015 17:30:00
值 - 10/20/2015 10:30:00 - UTC 10/20/2015 17:30:00
值 - 10/27/2015 10:30:00 - UTC 10/27/2015 17:30:00
值 -11/3/2015 10:30:00 - UTC 11/3/2015 17:30:00 (这应该是 18:30:00 !)
值 - 11/10/2015 10:30:00 - UTC 11/10/2015 17:30:00 (这应该是 18:30:00 !)

如您所见，最后两个的 UTC 时间应为 18:30:00。所以我想知道这是否只是 DDay Ical 的工作方式，我不应该指望它能正确获得 UTC 日期时间，或者我是否做错了什么。

Answer 1

由于夏令时，您会得到这个时差。一种可能的解决方案是不通过名称 Pacific Standard Time

获取时区

 // First load a file containing time zone information for Pacific Standard Time
var systemTimeZone = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time");

代替这个使用系统时区

var systemTimeZone = TimeZoneInfo.GetSystemTimeZones().FirstOrDefault();

或者简单地添加本地时区:

iCalendar iCalendar= new iCalendar();
iCalendar.AddLocalTimeZone();

要查找所有已注册的时区，click here

ReadOnlyCollection<TimeZoneInfo> zones = TimeZoneInfo.GetSystemTimeZones();
Console.WriteLine("The local system has the following {0} time zones", zones.Count);
foreach (TimeZoneInfo zone in zones)
   Console.WriteLine(zone.Id);

我只是在我的代码中使用 GetSystemTimeZones()

public static void Test1()
    {
        var systemTimeZone = TimeZoneInfo.GetSystemTimeZones().FirstOrDefault();
        //TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time");
        var icalTimeZone = iCalTimeZone.FromSystemTimeZone(systemTimeZone);

        var startTimeSearch = new DateTime(2015, 9, 8, 0, 0, 0, DateTimeKind.Utc);
        var endTimeSearch = new DateTime(2015, 12, 1, 00, 0, 0, DateTimeKind.Utc);

        var iCalendar = new iCalendar();
        var pacificTimeZone = iCalendar.AddTimeZone(icalTimeZone);

        var _event =
        new Event
        {
            Summary = "This is an event at 2015-09-08 10:30 PST (2015-09-08 17:30 UTC)",
            DTStart = new iCalDateTime(2015, 9, 8, 10, 30, 0, pacificTimeZone.TZID, iCalendar),
            Duration = new TimeSpan(0, 1, 0, 0)
        };

        var rp = new RecurrencePattern("FREQ=WEEKLY;UNTIL=20151112T080000Z;WKST=SU;BYDAY=TU");

        _event.RecurrenceRules.Add(rp);
        iCalendar.Events.Add(_event);

        var occurrences = iCalendar.GetOccurrences(startTimeSearch, endTimeSearch);
    }

当我调试时它得到了类似的输出

您可以相应地更改时区并获得结果。希望对你有帮助。