DDay图书馆是否正确计算循环规则？

Question

我做了一些测试。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：

10发生-以下是发生的Period.StartTime.Value和UTC特性

值- 9/8/2015 10:30- UTC 9/8/2015 17:30:00

值- 9/15/2015 10:30- UTC 9/15/2015 17:30:00

值- 9/22/2015 10:30- UTC 9/22/2015 17:30:00

值- 9/29/2015 10:30- UTC 9/29/2015 17:30:00

值- 10/6/2015 10:30- UTC 10/6/2015 17:30:00

值- 10/13/2015 10:30- UTC 10/13/2015 17:30:00

值- 10/20/2015 10:30- UTC 10/20/2015 17:30:00

值- 10/27/2015 10:30- UTC 10/27/2015 17:30:00

值 -11/3/2015 10:30- UTC 11/3/2015 17:30(这应该是18:30:00!)

值- 11/10/2015 10:30- UTC 11/10/2015 17:30(这应该是18:30:00!)

​

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正如你所看到的，最后两个世界协调时间应该是18:30:00。所以我想知道这是DDay的工作方式，我不应该指望它能使UTC的日期时间正确，或者我是否做错了什么。

Answer 1

由于日光节约，你得到了这个时差。一种可能的解决方案是不按名称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");

代替此使用系统时区，如

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

或者简单地添加本地时区：

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

若要查找所有已注册时区，单击此处

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);

我只是在代码中使用GetSystemTimeZones()，如下所示

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，它得到了输出，就像

​

​

您可以相应地更改时区并得到结果。希望它能帮到你。

Answer 2

不要使用dday.ical；使用ical.net。

这应该会让你开始：

var iCalendar = new Calendar();

var start = new DateTime(2015, 9, 8, 10, 30, 0);
var e = new Event
{
    Summary = "This is an event at 2015-09-08 10:30 PST (2015-09-08 17:30 UTC)",
    DtStart = new CalDateTime(start, "Pacific Standard Time"),
    Duration = TimeSpan.FromHours(1)
};

var rp = new RecurrencePattern("FREQ=WEEKLY;UNTIL=20151112T080000Z;WKST=SU;BYDAY=TU");
e.RecurrenceRules.Add(rp);
iCalendar.Events.Add(e);

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 occurrences = iCalendar.GetOccurrences(startTimeSearch, endTimeSearch);

结果：

​

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Answer 3

我可以解决这个问题。原来您不应该在ExceptionDates中指定时间，只需添加日期组件，

这似乎是可行的，GetOccurances现在正确地识别异常日期。希望这能帮助那些经历同样痛苦的人。