using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        var days = GetAllDayOfWeekPerMonth(7, 2017, DayOfWeek.Monday);

        Console.WriteLine(string.Join("\n", days.Select(x => x.ToString("dddd - MM/dd/yyyy"))));

    }

​

    public static IEnumerable<DateTime> GetAllDayOfWeekPerMonth(int month, int year, DayOfWeek dayOfWeek)

    {

        var date = new DateTime(year, month, 1);

        if(date.DayOfWeek != dayOfWeek)

        {

            int daysUntilDayOfWeek = ((int) dayOfWeek - (int) date.DayOfWeek + 7) % 7;

            date = date.AddDays(daysUntilDayOfWeek);

        }

        List<DateTime> days = new List<DateTime>();

        while(date.Month == month)

        {

            days.Add(date);

            date = date.AddDays(7);         

        }

        return days;

    }

}