DateTime.MaxDate can trip you up

Woil · **Posted:** Thu Jan 24, 2008 7:33 pm

Be careful when inserting a very precise datetime into SQL Server. (2000 or 2005, I think 2008 upped the precision on datetime.) Specifically be very careful when inserting a value of DateTime.MaxValue

If you assign MaxValue to your entity, save it, then later check for entity.Time == DateTime.MaxValue you'll probably get highly confused. This is easily solved by converting the MaxValue to the highest precision that SQL Server can handle. To do this I wrote an extension method for DateTime as follows:

Code:

    public static class DateTimeExtensions
    {
        public static DateTime ToSQLDateTime(this DateTime dt)
        {
            return new DateTime(dt.Ticks - (dt.Ticks % 10000000));            
        }
    }

Now it'll show up along with ToShortTimeString, ToLocalTime etc.

Code:

if(entity.Time == DateTime.MaxValue.ToSqlDateTime())

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