Get first day of week from DateTime in C# 28-12-2015 19:03:52 C# / Extensions 0 Bookmark(s) 368 View(s) public static class DateTimeExtensions { public static DateTime BeginOfWeek(this DateTime date) { int delta = DayOfWeek.Monday - date.DayOfWeek; if (delta > 0) { delta -= 7; } return date.AddDays(delta); } }