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

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 类的成员 Calendar

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 将添加到指定的 DateTime中。 如果 months 为负数,则生成的 DateTime 早于指定的 DateTime

如果生成的日期不是结果 DateTime 年份的月中的有效日期,则结果的日期部分将受到影响。 它更改为结果年份的结果月份中的最后一个有效日期。 如果生成的月份在指定 DateTime的年份之外,则结果DateTime的年份部分将受到影响。 如果生成的 DateTime 年份在指定 DateTime的纪元之外,则生成的 纪元部分将受到影响。 生成的 DateTime 的一天中的时间部分与指定的 DateTime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。 如果指定的月份为第 10 个月,则指定的日期为该月的第 31 天,参数的 months 值为 6,则生成的年份比指定的年份多 1,生成的月份为第 4 个月,生成的日期为第 30 天,即结果月份的最后一天。

如果 参数的 months 值为负值,则生成的 DateTime 早于指定的 DateTime

Kind返回DateTime值的 属性始终等于 DateTimeKind.Unspecified。 可以通过调用 DateTime.SpecifyKind 方法保留 Kind 参数的 time 属性,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