// Token: 0x060015ED RID: 5613 RVA: 0x000412E0 File Offset: 0x0003F4E0
        internal static StringBuilder FastFormatRfc1123(DateTime dateTime, TimeSpan offset, DateTimeFormatInfo dtfi)
        {
            StringBuilder stringBuilder = StringBuilderCache.Acquire(29);

            if (offset != DateTimeFormat.NullOffset)
            {
                dateTime -= offset;
            }
            int num;
            int num2;
            int num3;

            dateTime.GetDatePart(out num, out num2, out num3);
            stringBuilder.Append(DateTimeFormat.InvariantAbbreviatedDayNames[(int)dateTime.DayOfWeek]);
            stringBuilder.Append(',');
            stringBuilder.Append(' ');
            DateTimeFormat.AppendNumber(stringBuilder, (long)num3, 2);
            stringBuilder.Append(' ');
            stringBuilder.Append(DateTimeFormat.InvariantAbbreviatedMonthNames[num2 - 1]);
            stringBuilder.Append(' ');
            DateTimeFormat.AppendNumber(stringBuilder, (long)num, 4);
            stringBuilder.Append(' ');
            DateTimeFormat.AppendHHmmssTimeOfDay(stringBuilder, dateTime);
            stringBuilder.Append(' ');
            stringBuilder.Append("GMT");
            return(stringBuilder);
        }
 // Token: 0x060015EF RID: 5615 RVA: 0x00041424 File Offset: 0x0003F624
 private static void AppendHHmmssTimeOfDay(StringBuilder result, DateTime dateTime)
 {
     DateTimeFormat.AppendNumber(result, (long)dateTime.Hour, 2);
     result.Append(':');
     DateTimeFormat.AppendNumber(result, (long)dateTime.Minute, 2);
     result.Append(':');
     DateTimeFormat.AppendNumber(result, (long)dateTime.Second, 2);
 }
        // Token: 0x060015EE RID: 5614 RVA: 0x00041398 File Offset: 0x0003F598
        internal static StringBuilder FastFormatRoundtrip(DateTime dateTime, TimeSpan offset)
        {
            StringBuilder stringBuilder = StringBuilderCache.Acquire(28);
            int           num;
            int           num2;
            int           num3;

            dateTime.GetDatePart(out num, out num2, out num3);
            DateTimeFormat.AppendNumber(stringBuilder, (long)num, 4);
            stringBuilder.Append('-');
            DateTimeFormat.AppendNumber(stringBuilder, (long)num2, 2);
            stringBuilder.Append('-');
            DateTimeFormat.AppendNumber(stringBuilder, (long)num3, 2);
            stringBuilder.Append('T');
            DateTimeFormat.AppendHHmmssTimeOfDay(stringBuilder, dateTime);
            stringBuilder.Append('.');
            long val = dateTime.Ticks % 10000000L;

            DateTimeFormat.AppendNumber(stringBuilder, val, 7);
            DateTimeFormat.FormatCustomizedRoundripTimeZone(dateTime, offset, stringBuilder);
            return(stringBuilder);
        }