DateTime.AddDays() Method in C# Last Updated : 21 Jan, 2019 Comments Improve Suggest changes Like Article Like Report This method is used to return a new DateTime that adds the specified number of days to the value of this instance. Syntax: public DateTime AddDays (double value); Here, the value is the number of whole and fractional days. The value parameter can be negative or positive. Return Value: This method returns an object whose value is the sum of the date and time represented by this instance and the number of days represented by value. Exception: This method will give ArgumentOutOfRangeException if the resulting DateTime is less than MinValue or greater than MaxValue. Below programs illustrate the use of DateTime.AddDays(Double) Method: Example 1: csharp // C# program to demonstrate the // DateTime.AddDays(Double) Method using System; using System.Globalization; class GFG { // Main Method public static void Main() { try { // creating object of DateTime DateTime date1 = new DateTime(2010, 1, 1, 8, 0, 15); // adding the 36 days // using AddDays() method; DateTime date2 = date1.AddDays(36); // Display the date1 System.Console.WriteLine("DateTime before "+ "operation: {0:y} {0:dd}", date1); // Display the date2 System.Console.WriteLine("\nDateTime after"+ " operation: {0:y} {0:dd}", date2); } catch (ArgumentOutOfRangeException e) { Console.Write("Exception Thrown: "); Console.Write("{0}", e.GetType(), e.Message); } } } Output: DateTime before operation: 2010 January 01 DateTime after operation: 2010 February 06 Example 2: For ArgumentOutOfRangeException csharp // C# program to demonstrate the // DateTime.AddDays(Double) Method using System; using System.Globalization; class GFG { // Main Method public static void Main() { try { // creating object of DateTime and // initialize with MinValue DateTime date1 = DateTime.MaxValue; // Display the date1 Console.WriteLine("DateTime before "+ "operation: {0:y} {0:dd}", date1); // adding the TimeSpan of 36 days // using Add() method; System.DateTime date2 = date1.AddDays(36); // Display the date2 System.Console.WriteLine("\nDateTime after "+ "operation: {0:y} {0:dd}", date2); } catch (ArgumentOutOfRangeException e) { Console.WriteLine("\nThe resulting DateTime is "+ "greater than the DateTime.MaxValue "); Console.Write("Exception Thrown: "); Console.Write("{0}", e.GetType(), e.Message); } } } Output: DateTime before operation: 9999 December 31 The resulting DateTime is greater than the DateTime.MaxValue Exception Thrown: System.ArgumentOutOfRangeException Note: This method does not change the value of this DateTime. Instead, it returns a new DateTime whose value is the result of this operation. The fractional part of the value is the fractional part of a minute. For example, 7.5 is equivalent to 7 minutes, 30 seconds, 0 milliseconds, and 0 ticks. The value parameter is rounded to the nearest millisecond. Reference: https://docs.microsoft.com/en-us/dotnet/api/system.datetime.adddays?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article DateTime.AddDays() Method in C# R rohitprasad3 Follow Improve Article Tags : C# CSharp-method CSharp DateTime Struct Similar Reads DateTime.Add() Method in C# This method is used to return a new DateTime that adds the value of the specified TimeSpan to the value of this instance. Syntax: public DateTime Add (TimeSpan value); Here, value is a positive or negative time interval. Return Value: This method returns an object whose value is the sum of the date 2 min read DateTime.AddYears() Method in C# This method is used to returns a new DateTime that adds the specified number of years to the value of this instance. Syntax: public DateTime AddYears (int value); Here, the value is the number of years. The value parameter can be negative or positive. Return Value: This method returns an object whos 3 min read 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 wh 2 min read DateTime.AddHours() Method in C# This method is used to return a new DateTime that adds the specified number of hours to the value of this instance. Syntax: public DateTime AddHours (double value); Here, the value is the number of whole and fractional hours. The value parameter can be negative or positive. Return Value: This method 3 min read DateTime.AddSeconds() Method in C# This method is used to return a new DateTime that adds the specified number of seconds to the value of this instance. Syntax: public DateTime AddSeconds (double value); Here, value is a number of whole and fractional seconds. The value parameter can be negative or positive. Return Value: This method 2 min read Like