DateTimeOffset.AddDays() Method in C#

This method is used to return a new DateTimeOffset object that adds a specified number of whole and fractional days to the value of this instance.

Syntax: public DateTimeOffset AddDays (double days);
Here, it takes a number of whole and fractional days.

Return Value: This method returns an object whose value is the sum of the date and time represented by the current DateTimeOffset object and the number of days represented by days.

Exception: This method will give ArgumentOutOfRangeException if the resulting DateTimeOffset value is less than MinValue or the resulting DateTimeOffset value is greater than MaxValue.

Below programs illustrate the use of DateTimeOffset.AddDays(Double) Method:

Example 1:

// C# program to demonstrate the
// DateTimeOffset.AddDays(Double)
// Method
using System;
using System.Globalization;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // creating object of  DateTimeOffset
            DateTimeOffset offset = new DateTimeOffset(2007, 6, 1, 7, 55, 0,
                                                     new TimeSpan(-5, 0, 0));

            // adding a specified number of whole
            // and fractional days to the value
            // of this instance using AddDays(Double)
            // method
            DateTimeOffset value = offset.AddDays(10);

            // Display the time
            Console.WriteLine("DateTimeOffset is {0}", value);
        }

        catch (ArgumentOutOfRangeException e) {
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

DateTimeOffset is 06/11/2007 07:55:00 -05:00

Example 2: For ArgumentOutOfRangeException

// C# program to demonstrate the
// DateTimeOffset.AddDays(Double)
// Method
using System;
using System.Globalization;

class GFG {

    // Main Method
    public static void Main()
    {
        try {

            // creating object of  DateTimeOffset
            DateTimeOffset offset = DateTimeOffset.MaxValue;

            // adding a specified number of whole and
            // fractional days to the value of this instance.
            // using AddDays(Double) method;
            DateTimeOffset value = offset.AddDays(10);

            // Display the time
            Console.WriteLine("DateTimeOffset is {0}", value);
        }

        catch (ArgumentOutOfRangeException e) {
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

Exception Thrown: System.ArgumentOutOfRangeException

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.datetimeoffset.adddays?view=netframework-4.7.2