Returns a new DateTime that adds the specified number of seconds to the value of this instance.
An object whose value is the sum of the date and time represented by this instance and the number of seconds represented by value.
Type Reason ArgumentException The resulting DateTime is less than DateTime.MinValue or greater than DateTime.MaxValue.
The fractional part of value is the fractional part of a second. For example, 4.5 is equivalent to 4 seconds, 500 milliseconds, and 0 ticks.
The value parameter is rounded to the nearest millisecond.