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 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 DateTime

months
Int32

要添加的月数。

返回

DateTime

将指定月数添加到指定的 DateTime 中时得到的 DateTime

例外

得到的 DateTime 超出了此日历支持的范围。

months 超出了 DateTime 返回值支持的范围。

示例

下面的代码示例演示类 Calendar 的成员。

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

该值 months 将添加到指定的 DateTime值。 如果 months 为负值,则生成的结果 DateTime 早于指定的 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,则生成的 DateTime 日期部分会受到影响。 它更改为生成的年份的最后一个有效日。 如果生成的月份超出指定DateTime年份,则生成的DateTime年份部分将受到影响。 如果生成的年份不在指定DateTime年份之外,则结果DateTime的纪元部分会受到影响。 生成的 DateTime 当天部分与指定的 DateTime时间保持相同。

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。 如果指定月份为第十个月,则指定日为该月的第 31 天,参数的值为 months 6,生成的年份是指定年份的一个以上,生成的月份为第四个月,生成的日期为第 30 天,这是生成的月份的最后一天。

如果参数的值 months 为负值,则生成的结果 DateTime 早于指定的 DateTime值。

Kind返回DateTime值的属性始终相等DateTimeKind.Unspecified。 可以通过调用DateTime.SpecifyKind方法来保留Kind参数的属性time,如以下示例所示。

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