public static DateTimeOffset ParseExact(ReadOnlySpan <char> input, ReadOnlySpan <char> format, IFormatProvider?formatProvider, DateTimeStyles styles = DateTimeStyles.None)
{
styles = ValidateStyles(styles, nameof(styles));
DateTime dateResult = DateTimeParse.ParseExact(input, format, DateTimeFormatInfo.GetInstance(formatProvider), styles, out TimeSpan offset);
return(new DateTimeOffset(dateResult.Ticks, offset));
}