Extracting dates of current week using .Net?

Question

I am trying to extract dates for current week's days and I just can't find a sensible, smart way instead of a long case, switches and if statements. Anybody knows a relatively easy way to extract those using .Net? Thanks!

Show what did you tried and why you search for another aproach — Fabio, Jun 07 '15 at 09:47
Haven't started yet, I have a mental image of cycling through every day and adding or substracting days according to the "Today" value. I just hope there's a more reasonable approach — Pavel Zagalsky, Jun 07 '15 at 09:50
Try `DateTime.Now.DayOfWeek` and then based on the result count another dates of the same week — Fabio, Jun 07 '15 at 09:52
The concept of "week" is a fuzzy concept due to the fact that many cultures have different notions about when the week starts. Could you clarify if this is for a particular culture or whether you need a culture-independent solution? For instance, are you making a general purpose class library or are you making an application that will only have to handle Israeli weeks? — Lasse V. Karlsen, Jun 07 '15 at 10:43
I need the Israeli one that starts on Sunday and ends on Saturday — Pavel Zagalsky, Jun 07 '15 at 13:41

Sami Kuhmonen · Answer 1 · 2015-06-07T13:55:08.993

3

The DateTime.DayOfWeek is an enumeration that starts with Sunday being 0 and going forward. If you take today's day-of-week, it will also tell how many days ago Sunday was. Therefore going back that many days will give you the Sunday of this week, assuming week starts on Sunday. You can go forward from that for the seven days of the week.

var today = DateTime.Now;
var thisSunday = today.AddDays(-(int)today.DayOfWeek);

for (int i=0; i<7; i++)
  Console.WriteLine(thisSunday.AddDays(i).ToString());

If the week starts from Monday, use

var thisMonday = today.AddDays(-(((int)today.DayOfWeek + 6) % 7));

edited Jun 07 '15 at 13:55

answered Jun 07 '15 at 09:52

Sami Kuhmonen

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Hmm interesting.. I think this solution might do the trick.. Thanks a lot buddy! – Pavel Zagalsky Jun 07 '15 at 10:01
It would probably be better to branch out in both directions from the given date and inspecting the week number, this way you would have code that would be culture independent. Not all cultures starts their weeks on sundays. – Lasse V. Karlsen Jun 07 '15 at 10:41
@LasseV.Karlsen Yes, that's why I added a variant for weeks starting from Mondays. It can also be easily modified to start from a desired weekday if necessary. – Sami Kuhmonen Jun 07 '15 at 10:44
@SamiKuhmonen Can you please explain me this part? today.AddDays(-(int)today.DayOfWeek)? And what can I do to implement This Week function with the same process? Cheers! – Pavel Zagalsky Jun 07 '15 at 13:46
@PavelZagalsky Wrote about how the logic – Sami Kuhmonen Jun 07 '15 at 13:56
Ah I Found a way, my mistake – Pavel Zagalsky Jun 07 '15 at 14:12

score 0 · Answer 2 · edited May 23 '17 at 11:51

You may use extension method to set the day that week start with (credit goes to @Compile This)

public static class DateTimeExtensions
{
    public static DateTime StartOfWeek(this DateTime datetime, DayOfWeek startOfWeek)
    {
        int difference = datetime.DayOfWeek - startOfWeek;
        if (difference >= 0)
            return datetime.AddDays(-1 * difference).Date;
        difference += 7;
        return datetime.AddDays(-1 * difference).Date;
    }
}

Then you can get date of the week using same loop as @Sami_Kuhmonen mentioned:

        DateTime d = DateTime.Now.StartOfWeek(DayOfWeek.Saturday);
        for (int i = 0; i < 7; i++)
            Console.WriteLine(d.AddDays(i));

Extracting dates of current week using .Net?

2 Answers2