Question

I am sure this has been done before so i am looking for an efficient solution instead of own custom solution.

Given 2 dates, I am trying to generate the accurate weekly date (for creating weekly orders).

EDIT: I need to use .NET standard library to do this.

Example below,

Given 28/02/2012 and 6/03/2012.

so, the weekly dates generated are
- Week From(Start Monday):   Week To(End Sunday):
- 27/02/2012               - 04/03/2012
- 05/03/2012               - 11/03/2012

Another example (1 month)

Given 01/02/2012 and 29/02/2012
so, the weekly dates generated are
- Week From(Start Monday):   Week To(End Sunday):
- 30/01/2012               - 05/02/2012
- 06/02/2012               - 12/02/2012
- 13/02/2012               - 19/02/2012
- 20/02/2012               - 26/02/2012
- 27/02/2012               - 04/03/2012

I am doing this in c#. Has this been done before? Mind sharing the solutions?

Cheers

Answer 1

Here’s a solution using Noda Time. Admittedly it requires a <= operator which I’m just implementing right now – but that shouldn’t take long 🙂

using System;
using NodaTime;

class Test
{
    static void Main()
    {
        ShowDates(new LocalDate(2012, 2, 28), new LocalDate(2012, 3, 6));
        ShowDates(new LocalDate(2012, 2, 1), new LocalDate(2012, 2, 29));
    }

    static void ShowDates(LocalDate start, LocalDate end)
    {
        // Previous is always strict - increment start so that
        // it *can* be the first day, then find the previous
        // Monday
        var current = start.PlusDays(1).Previous(IsoDayOfWeek.Monday);
        while (current <= end)
        {
            Console.WriteLine("{0} - {1}", current,
                              current.Next(IsoDayOfWeek.Sunday));
            current = current.PlusWeeks(1);
        }
    }
}

Obviously it’s possible to do this in normal DateTime as well, but there’s no real representation of “just a date” which makes the code less clear – and you’d need to implement Previous yourself.

EDIT: For example, in this case you might use:

using System;

class Test
{
    static void Main()
    {
        ShowDates(new DateTime(2012, 2, 28), new DateTime(2012, 3, 6));
        ShowDates(new DateTime(2012, 2, 1), new DateTime(2012, 2, 29));
    }

    static void ShowDates(DateTime start, DateTime end)
    {
        // In DateTime, 0=Sunday
        var daysToSubtract = ((int) start.DayOfWeek + 6) % 7;
        var current = start.AddDays(-daysToSubtract);        

        while (current <= end)
        {
            Console.WriteLine("{0} - {1}", current, current.AddDays(6));
            current = current.AddDays(7);
        }
    }
}