Freigeben über


Calendar.AddYears Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

When overridden in a derived class, returns a DateTime that is the specified number of years away from the specified DateTime.

Namespace:  System.Globalization
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public MustOverride Function AddYears ( _
    time As DateTime, _
    years As Integer _
) As DateTime
public abstract DateTime AddYears(
    DateTime time,
    int years
)

Parameters

Return Value

Type: System.DateTime
The DateTime that results from adding the specified number of years to the specified DateTime.

Exceptions

Exception Condition
ArgumentException

The resulting DateTime is outside the supported range of this calendar.

ArgumentOutOfRangeException

years is outside the supported range of the DateTime return value.

Remarks

The years value is added to the specified DateTime. If years is negative, the resulting DateTime is earlier than the specified DateTime.

The day part of the resulting DateTime is affected if the resulting day is not a valid day in the resulting month of the resulting year. It is changed to the last valid day in the resulting month of the resulting year. The month part of the resulting DateTime is affected if the resulting month is not a valid month in the resulting year. It is changed to the last valid month in the resulting year. The era part of the resulting DateTime is affected if the resulting year is outside the era of the specified DateTime. The time-of-day part of the resulting DateTime remains the same as the specified DateTime.

For example, in the Gregorian calendar, February has 28 days, except during a leap year when it has 29 days. If the specified date is the 29th day of February in a leap year and the value of years is 1, the resulting date is the 28th day of February in the following year.

If years is negative, the resulting DateTime is earlier than the specified DateTime.

The Kind property of the returned DateTime value always equals DateTimeKind.Unspecified. You can preserve the Kind property of the time parameter by calling the DateTime.SpecifyKind method, as the following example shows.

returnTime = DateTime.SpecifyKind(cal.AddYears(time, years), time.Kind)
returnTime = DateTime.SpecifyKind(cal.AddYears(time, years), time.Kind);

Examples

The following code example demonstrates the members of the Calendar class.

Imports System.Globalization

Public Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

      ' Sets a DateTime to April 3, 2002 of the Gregorian calendar.
      Dim myDT As New DateTime(2002, 4, 3, New GregorianCalendar())

      ' Uses the default calendar of the InvariantCulture.
      Dim myCal As Calendar = CultureInfo.InvariantCulture.Calendar

      ' Displays the values of the DateTime.
      outputBlock.Text += String.Format("April 3, 2002 of the Gregorian calendar:") & vbCrLf
      DisplayValues(outputBlock, myCal, myDT)

      ' Adds 5 to every component of the DateTime.
      myDT = myCal.AddYears(myDT, 5)
      myDT = myCal.AddMonths(myDT, 5)
      myDT = myCal.AddWeeks(myDT, 5)
      myDT = myCal.AddDays(myDT, 5)
      myDT = myCal.AddHours(myDT, 5)
      myDT = myCal.AddMinutes(myDT, 5)
      myDT = myCal.AddSeconds(myDT, 5)
      myDT = myCal.AddMilliseconds(myDT, 5)

      ' Displays the values of the DateTime.
      outputBlock.Text &= "After adding 5 to each component of the DateTime:" & vbCrLf
      DisplayValues(outputBlock, myCal, myDT)

   End Sub 

   Public Shared Sub DisplayValues(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal myCal As Calendar, ByVal myDT As DateTime)
      outputBlock.Text += String.Format("   Era:          {0}", myCal.GetEra(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   Year:         {0}", myCal.GetYear(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   Month:        {0}", myCal.GetMonth(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   DayOfYear:    {0}", myCal.GetDayOfYear(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   DayOfMonth:   {0}", myCal.GetDayOfMonth(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   DayOfWeek:    {0}", myCal.GetDayOfWeek(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   Hour:         {0}", myCal.GetHour(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   Minute:       {0}", myCal.GetMinute(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   Second:       {0}", myCal.GetSecond(myDT)) & vbCrLf
      outputBlock.Text += String.Format("   Milliseconds: {0}", myCal.GetMilliseconds(myDT)) & vbCrLf
      outputBlock.Text &= vbCrLf
   End Sub 
End Class  
' This example produces the following output.
'       April 3, 2002 of the Gregorian calendar:
'          Era:          1
'          Year:         2002
'          Month:        4
'          DayOfYear:    93
'          DayOfMonth:   3
'          DayOfWeek:    Wednesday
'          Hour:         0
'          Minute:       0
'          Second:       0
'          Milliseconds: 0
'       
'       After adding 5 to each component of the DateTime:
'          Era:          1
'          Year:         2007
'          Month:        10
'          DayOfYear:    286
'          DayOfMonth:   13
'          DayOfWeek:    Saturday
'          Hour:         5
'          Minute:       5
'          Second:       5
'          Milliseconds: 5
using System;
using System.Globalization;


public class Example
{

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {

      // Sets a DateTime to April 3, 2002 of the Gregorian calendar.
      DateTime myDT = new DateTime(2002, 4, 3, new GregorianCalendar());

      // Uses the default calendar of the InvariantCulture.
      Calendar myCal = CultureInfo.InvariantCulture.Calendar;

      // Displays the values of the DateTime.
      outputBlock.Text += String.Format("April 3, 2002 of the Gregorian calendar:") + "\n";
      DisplayValues(outputBlock, myCal, myDT);

      // Adds 5 to every component of the DateTime.
      myDT = myCal.AddYears(myDT, 5);
      myDT = myCal.AddMonths(myDT, 5);
      myDT = myCal.AddWeeks(myDT, 5);
      myDT = myCal.AddDays(myDT, 5);
      myDT = myCal.AddHours(myDT, 5);
      myDT = myCal.AddMinutes(myDT, 5);
      myDT = myCal.AddSeconds(myDT, 5);
      myDT = myCal.AddMilliseconds(myDT, 5);

      // Displays the values of the DateTime.
      outputBlock.Text += "After adding 5 to each component of the DateTime:" + "\n";
      DisplayValues(outputBlock, myCal, myDT);

   }

   public static void DisplayValues(System.Windows.Controls.TextBlock outputBlock, Calendar myCal, DateTime myDT)
   {
      outputBlock.Text += String.Format("   Era:          {0}", myCal.GetEra(myDT)) + "\n";
      outputBlock.Text += String.Format("   Year:         {0}", myCal.GetYear(myDT)) + "\n";
      outputBlock.Text += String.Format("   Month:        {0}", myCal.GetMonth(myDT)) + "\n";
      outputBlock.Text += String.Format("   DayOfYear:    {0}", myCal.GetDayOfYear(myDT)) + "\n";
      outputBlock.Text += String.Format("   DayOfMonth:   {0}", myCal.GetDayOfMonth(myDT)) + "\n";
      outputBlock.Text += String.Format("   DayOfWeek:    {0}", myCal.GetDayOfWeek(myDT)) + "\n";
      outputBlock.Text += String.Format("   Hour:         {0}", myCal.GetHour(myDT)) + "\n";
      outputBlock.Text += String.Format("   Minute:       {0}", myCal.GetMinute(myDT)) + "\n";
      outputBlock.Text += String.Format("   Second:       {0}", myCal.GetSecond(myDT)) + "\n";
      outputBlock.Text += String.Format("   Milliseconds: {0}", myCal.GetMilliseconds(myDT)) + "\n";
      outputBlock.Text += "\n";
   }

}


/*
This code produces the following output.

April 3, 2002 of the Gregorian calendar:
   Era:          1
   Year:         2002
   Month:        4
   DayOfYear:    93
   DayOfMonth:   3
   DayOfWeek:    Wednesday
   Hour:         0
   Minute:       0
   Second:       0
   Milliseconds: 0

After adding 5 to each component of the DateTime:
   Era:          1
   Year:         2007
   Month:        10
   DayOfYear:    286
   DayOfMonth:   13
   DayOfWeek:    Saturday
   Hour:         5
   Minute:       5
   Second:       5
   Milliseconds: 5

*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.