/// <summary>
/// Previous
/// </summary>
/// <param name="ldt"></param>
/// <param name="dayOfWeek"></param>
/// <returns></returns>
public static LocalDateTime Previous(this LocalDateTime ldt, DayOfWeek dayOfWeek)
{
do
{
ldt = ldt.PreviousDay();
} while (ldt.DayOfWeek != dayOfWeek.AsIsoDayOfWeek());
return(ldt);
}