get date from week number and year in c# code example

Example 1: get what week of the month c#

static int GetWeekNumberOfMonth(DateTime date)
{
    date = date.Date;
    DateTime firstMonthDay = new DateTime(date.Year, date.Month, 1);
    DateTime firstMonthMonday = firstMonthDay.AddDays((DayOfWeek.Monday + 7 - firstMonthDay.DayOfWeek) % 7);
    if (firstMonthMonday > date)
    {
        firstMonthDay = firstMonthDay.AddMonths(-1);
        firstMonthMonday = firstMonthDay.AddDays((DayOfWeek.Monday + 7 - firstMonthDay.DayOfWeek) % 7);
    }
    return (date - firstMonthMonday).Days / 7 + 1;
}

Example 2: get days of week of a date c#

// This example demonstrates the DateTime.DayOfWeek property
using System;

class Sample
{
    public static void Main()
    {
// Assume the current culture is en-US.
// Create a DateTime for the first of May, 2003.
    DateTime dt = new DateTime(2003, 5, 1);
    Console.WriteLine("Is Thursday the day of the week for {0:d}?: {1}",
                       dt, dt.DayOfWeek == DayOfWeek.Thursday);
    Console.WriteLine("The day of the week for {0:d} is {1}.", dt, dt.DayOfWeek);
    }
}
/*
This example produces the following results:

Is Thursday the day of the week for 5/1/2003?: True
The day of the week for 5/1/2003 is Thursday.
*/