Question

如果我有一个约会列表，并希望在几周内获得这些约会，例如。

public class appointments
{
     public string Appointment { get; set; }
     public DateTime Start { get; set; }
     public string Location { get; set; }
}

List<appointments> appointment = new List<appointments>();

appointment.Add(new appointments() { Appointment = "meeting", Start = new DateTime(2013, 01,02), Location = "office"});
appointment.Add(new appointments() { Appointment = "lunch",  Start = new DateTime(2013, 01, 07), Location = "cafe" });
appointment.Add(new appointments() { Appointment = "meeting", Start = new DateTime(2013, 01, 08), Location = "cityhall" });
appointment.Add(new appointments() { Appointment = "dentist", Start = new DateTime(2013, 01, 14), Location = "dentist" });

现在我想要一个从2013-01-02到2013-01-25的时间段，并且startdate 01-02将是开始周。

所以02到08之间的项目是一周09-16另一个，依此类推，直到结束，其中一周有7天。我怎么能迭代列表并将特定的周传递给另一个方法而不预先计算“周制动日期”只需要添加7天直到结束？

Answer 1

以下代码在第1周返回“牙医”，第0周返回“会议，午餐，会议”。

class Program
{
    static void Main(string[] args)
    {
        List<appointments> appointment = new List<appointments>();

        appointment.Add(new appointments() { Appointment = "meeting", Start = new DateTime(2013, 01, 02), Location = "office" });
        appointment.Add(new appointments() { Appointment = "lunch", Start = new DateTime(2013, 01, 07), Location = "cafe" });
        appointment.Add(new appointments() { Appointment = "meeting", Start = new DateTime(2013, 01, 08), Location = "cityhall" });
        appointment.Add(new appointments() { Appointment = "dentist", Start = new DateTime(2013, 01, 14), Location = "dentist" });

        foreach (var appt in GetAppointmentsByWeek(appointment, 1))
            Console.WriteLine(appt.Appointment);

        Console.ReadLine();
    }

    private static IEnumerable<appointments> GetAppointmentsByWeek(List<appointments> appts, int weeknum)
    {
        if (weeknum < 0)
            return new appointments[] { };

        var ordered = appts.OrderBy(a => a.Start.Ticks);           
        var start = ordered.First().Start.AddDays(weeknum * 7);
        var end = start.AddDays(7);
        return ordered.Where(o => o.Start.Ticks >= start.Ticks && o.Start.Ticks <= end.Ticks);
    }
}

public class appointments
{
    public string Appointment { get; set; }
    public DateTime Start { get; set; }
    public string Location { get; set; }
}

Answer 2

您可以在约会上使用GroupBy按特定周分组。这段代码是未经测试和免费的，但您应该明白这一点。

private static IEnumerable<appointments> GetAppointmentsByWeek(List<appointments> appts, int weeknum)
{
    var WeekGroup = appts.GroupBy(ap => GetWeekOfYear(ap.Start)).Where(gp => gp.Key == weeknum).FirstOrDefault();

    if (WeekGroup == null) {return new List<appointments>();} //No appointments for this week

    return WeekGroup.Select(gp => gp.ToList());
}

您需要实施GetWeekOfYear（http://msdn.microsoft.com/en-us/library/system.globalization.calendar.getweekofyear.aspx） - 但是对于任何给定的约会列表和给定的周数，这将返回该周的所有约会。

循环通过时间段来获得数周

2 个答案: