Calendar.AddMonths(DateTime, Int32) 方法

定义

当在派生类中重写时,将返回与指定 DateTime 相距指定月数的 DateTimeWhen overridden in a derived class, returns a DateTime that is the specified number of months away from the specified DateTime.

public:
 abstract DateTime AddMonths(DateTime time, int months);
public abstract DateTime AddMonths (DateTime time, int months);
abstract member AddMonths : DateTime * int -> DateTime
Public MustOverride Function AddMonths (time As DateTime, months As Integer) As DateTime

参数

time
DateTime

将向其添加月数的 DateTimeThe DateTime to which to add months.

months
Int32

要添加的月数。The number of months to add.

返回

DateTime

将指定月数添加到指定的 DateTime 中时得到的 DateTimeThe DateTime that results from adding the specified number of months to the specified DateTime.

例外

得到的 DateTime 超出了此日历支持的范围。The resulting DateTime is outside the supported range of this calendar.

months 超出了 DateTime 返回值支持的范围。months is outside the supported range of the DateTime return value.

示例

下面的代码示例演示类的成员 CalendarThe following code example demonstrates the members of the Calendar class.

using namespace System;
using namespace System::Globalization;
void DisplayValues( Calendar^ myCal, DateTime myDT )
{
   Console::WriteLine( "   Era: {0}", myCal->GetEra( myDT ) );
   Console::WriteLine( "   Year: {0}", myCal->GetYear( myDT ) );
   Console::WriteLine( "   Month: {0}", myCal->GetMonth( myDT ) );
   Console::WriteLine( "   DayOfYear: {0}", myCal->GetDayOfYear( myDT ) );
   Console::WriteLine( "   DayOfMonth: {0}", myCal->GetDayOfMonth( myDT ) );
   Console::WriteLine( "   DayOfWeek: {0}", myCal->GetDayOfWeek( myDT ) );
   Console::WriteLine( "   Hour: {0}", myCal->GetHour( myDT ) );
   Console::WriteLine( "   Minute: {0}", myCal->GetMinute( myDT ) );
   Console::WriteLine( "   Second: {0}", myCal->GetSecond( myDT ) );
   Console::WriteLine( "   Milliseconds: {0}", myCal->GetMilliseconds( myDT ) );
   Console::WriteLine();
}

int main()
{
   
   // Sets a DateTime to April 3, 2002 of the Gregorian calendar.
   DateTime myDT = DateTime(2002,4,3,gcnew GregorianCalendar);
   
   // Uses the default calendar of the InvariantCulture.
   Calendar^ myCal = CultureInfo::InvariantCulture->Calendar;
   
   // Displays the values of the DateTime.
   Console::WriteLine( "April 3, 2002 of the Gregorian calendar:" );
   DisplayValues( 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.
   Console::WriteLine( "After adding 5 to each component of the DateTime:" );
   DisplayValues( myCal, myDT );
}

/*
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

*/
using System;
using System.Globalization;

public class SamplesCalendar  {

   public static void Main()  {

      // 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.
      Console.WriteLine( "April 3, 2002 of the Gregorian calendar:" );
      DisplayValues( 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.
      Console.WriteLine( "After adding 5 to each component of the DateTime:" );
      DisplayValues( myCal, myDT );
   }

   public static void DisplayValues( Calendar myCal, DateTime myDT )  {
      Console.WriteLine( "   Era:          {0}", myCal.GetEra( myDT ) );
      Console.WriteLine( "   Year:         {0}", myCal.GetYear( myDT ) );
      Console.WriteLine( "   Month:        {0}", myCal.GetMonth( myDT ) );
      Console.WriteLine( "   DayOfYear:    {0}", myCal.GetDayOfYear( myDT ) );
      Console.WriteLine( "   DayOfMonth:   {0}", myCal.GetDayOfMonth( myDT ) );
      Console.WriteLine( "   DayOfWeek:    {0}", myCal.GetDayOfWeek( myDT ) );
      Console.WriteLine( "   Hour:         {0}", myCal.GetHour( myDT ) );
      Console.WriteLine( "   Minute:       {0}", myCal.GetMinute( myDT ) );
      Console.WriteLine( "   Second:       {0}", myCal.GetSecond( myDT ) );
      Console.WriteLine( "   Milliseconds: {0}", myCal.GetMilliseconds( myDT ) );
      Console.WriteLine();
   }
}


/*
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

*/
Imports System.Globalization


Public Class SamplesCalendar   

   Public Shared Sub Main()

      ' 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.
      Console.WriteLine("April 3, 2002 of the Gregorian calendar:")
      DisplayValues(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.
      Console.WriteLine("After adding 5 to each component of the DateTime:")
      DisplayValues(myCal, myDT)

   End Sub

   Public Shared Sub DisplayValues(myCal As Calendar, myDT As DateTime)
      Console.WriteLine("   Era:          {0}", myCal.GetEra(myDT))
      Console.WriteLine("   Year:         {0}", myCal.GetYear(myDT))
      Console.WriteLine("   Month:        {0}", myCal.GetMonth(myDT))
      Console.WriteLine("   DayOfYear:    {0}", myCal.GetDayOfYear(myDT))
      Console.WriteLine("   DayOfMonth:   {0}", myCal.GetDayOfMonth(myDT))
      Console.WriteLine("   DayOfWeek:    {0}", myCal.GetDayOfWeek(myDT))
      Console.WriteLine("   Hour:         {0}", myCal.GetHour(myDT))
      Console.WriteLine("   Minute:       {0}", myCal.GetMinute(myDT))
      Console.WriteLine("   Second:       {0}", myCal.GetSecond(myDT))
      Console.WriteLine("   Milliseconds: {0}", myCal.GetMilliseconds(myDT))
      Console.WriteLine()
   End Sub

End Class


'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

注解

months该值将添加到指定的 DateTime 中。The months value is added to the specified DateTime. 如果 months 为负,则生成的 DateTime 早于指定的 DateTimeIf months is negative, the resulting DateTime is earlier than the specified DateTime.

如果生成的日期不是结果年份的结果月份中的有效日期,则结果中的日部分 DateTime 会受到影响。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. 它将更改为生成的年份中的最后一个有效日。It is changed to the last valid day in the resulting month of the resulting year. 如果生成的月份超出了指定的年份,则结果中的年份部分 DateTime 会受到影响 DateTimeThe year part of the resulting DateTime is affected if the resulting month is outside the year of the specified DateTime. DateTime如果结果年份在指定的纪元以外,则会影响得到的纪元部分 DateTimeThe era part of the resulting DateTime is affected if the resulting year is outside the era of the specified DateTime. 生成的的时间部分与 DateTime 指定的相同 DateTimeThe time-of-day part of the resulting DateTime remains the same as the specified DateTime.

例如,假设当前日历有12个月,其中第四个月有30天,第十个月有31天。For example, suppose that the current calendar has 12 months, where the fourth month has 30 days and the tenth month has 31 days. 如果指定的月份是第十个月,则指定的日期是该月的第31天,并且参数的值 months 为6,所得的年份比指定年份多一,生成的月份是第四个月,而结果日为第30天,即结果月份的最后一天。If the specified month is the tenth month, the specified day is the 31st day of that month, and the value of the months parameter is 6, the resulting year is one more than the specified year, the resulting month is the fourth month, and the resulting day is the 30th day, which is the last day of the resulting month.

如果参数的值 months 为负,则生成的值 DateTime 早于指定的 DateTimeIf the value of the months parameter is negative, the resulting DateTime is earlier than the specified DateTime.

Kind返回的值的属性 DateTime 始终相等 DateTimeKind.UnspecifiedThe Kind property of the returned DateTime value always equals DateTimeKind.Unspecified. 可以 Kind time 通过调用方法来保留参数的属性 DateTime.SpecifyKind ,如下面的示例所示。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.AddMonths(time, months), time.Kind);
returnTime = DateTime.SpecifyKind(cal.AddMonths(time, months), time.Kind)

适用于

另请参阅