UmAlQuraCalendar.AddMonths Method
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Updated: October 2010
Calculates a date that is a specified number of months away from a specified initial date.
Namespace: System.Globalization
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Overrides Function AddMonths ( _
time As DateTime, _
months As Integer _
) As DateTime
public override DateTime AddMonths(
DateTime time,
int months
)
Parameters
- time
Type: System.DateTime
The date to which to add months. The UmAlQuraCalendar class supports only dates from 04/30/1900 00.00.00 (Gregorian date) through 05/13/2029 23:59:59 (Gregorian date).
- months
Type: System.Int32
The positive or negative number of months to add.
Return Value
Type: System.DateTime
The date yielded by adding the number of months specified by the months parameter to the date specified by the time parameter.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentException | The resulting date is outside the range supported by the UmAlQuraCalendar class. |
| ArgumentOutOfRangeException | months is less than -120,000 or greater than 120,000. -or- time is outside the range supported by this calendar. |
Remarks
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 year part of the resulting DateTime is affected if the resulting month is outside the year of the specified DateTime. This implementation supports only the current era. Therefore, an exception is thrown 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, if the specified month is Zulkadah, which has 30 days, the specified day is the 30th day of that month, and the value of the months parameter is 3, the resulting year is one more than the specified year, the resulting month is Safar, and the resulting day is the 29th day, which is the last day in Safar.
If the value of the months parameter is negative, the resulting DateTime is earlier than the specified DateTime.
The UmAlQuraCalendar class supports only dates from 04/30/1900 00.00.00 (Gregorian date) through 05/13/2029 23:59:59 (Gregorian date). An ArgumentOutOfRangeException is thrown if the calendar attempts to handle any date outside that range.
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.AddMonths(time, months), time.Kind)
returnTime = DateTime.SpecifyKind(cal.AddMonths(time, months), time.Kind);
Examples
The following example instantiates a DateTime value and displays the values of several of its components in the Um Al Qura calendar. Next, it calls the AddYears and AddMonths methods to add 2 years and 10 months in the Um Al Qura calendar to the date value. Finally, it again displays the values of these date components in the Um Al Qura calendar.
Imports System.Globalization
Module Example
Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
Dim date1 As Date = New Date(2011, 4, 3, New GregorianCalendar())
Dim cal As New UmAlQuraCalendar()
outputBlock.Text &= String.Format("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:",
date1) & vbCrLf
DisplayCalendarInfo(outputBlock, cal, date1)
' Add 2 years and 10 months by calling UmAlQuraCalendar methods.
date1 = cal.AddYears(date1, 2)
date1 = cal.AddMonths(date1, 10)
outputBlock.Text += String.Format("After adding 2 years and 10 months in the {0} calendar,",
GetCalendarName(cal)) & vbCrLf
outputBlock.Text &= String.Format("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:",
date1) & vbCrLf
DisplayCalendarInfo(outputBlock, cal, date1)
End Sub
Private Sub DisplayCalendarInfo(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal cal As Calendar, ByVal date1 As Date)
outputBlock.Text += String.Format(" Calendar: {0}", GetCalendarName(cal)) & vbCrLf
outputBlock.Text += String.Format(" Era: {0}", cal.GetEra(date1)) & vbCrLf
outputBlock.Text += String.Format(" Year: {0}", cal.GetYear(date1)) & vbCrLf
outputBlock.Text += String.Format(" Month: {0}", cal.GetMonth(date1)) & vbCrLf
outputBlock.Text += String.Format(" DayOfYear: {0}", cal.GetDayOfYear(date1)) & vbCrLf
outputBlock.Text += String.Format(" DayOfMonth: {0}", cal.GetDayOfMonth(date1)) & vbCrLf
outputBlock.Text += String.Format(" DayOfWeek: {0}", cal.GetDayOfWeek(date1)) & vbCrLf
outputBlock.Text &= vbCrLf
End Sub
Private Function GetCalendarName(ByVal cal As Calendar) As String
Return cal.ToString().Replace("System.Globalization.", "").
Replace("Calendar", "")
End Function
End Module
' The example displays the following output:
' April 3, 2011 in the Gregorian calendar is equivalent to:
' Calendar: UmAlQura
' Era: 1
' Year: 1432
' Month: 4
' DayOfYear: 118
' DayOfMonth: 29
' DayOfWeek: Sunday
'
' After adding 2 years and 10 months in the UmAlQura calendar,
' January 1, 2014 in the Gregorian calendar is equivalent to:
' Calendar: UmAlQura
' Era: 1
' Year: 1435
' Month: 2
' DayOfYear: 59
' DayOfMonth: 29
' DayOfWeek: Wednesday
using System;
using System.Globalization;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
DateTime date1 = new DateTime(2011, 4, 3, new GregorianCalendar());
Calendar cal = new UmAlQuraCalendar();
outputBlock.Text += String.Format("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:\n",
date1);
DisplayCalendarInfo(outputBlock, cal, date1);
// Add 2 years and 10 months by calling UmAlQuraCalendar methods.
date1 = cal.AddYears(date1, 2);
date1 = cal.AddMonths(date1, 10);
outputBlock.Text += String.Format("After adding 2 years and 10 months in the {0} calendar,\n",
GetCalendarName(cal));
outputBlock.Text += String.Format("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:\n",
date1);
DisplayCalendarInfo(outputBlock, cal, date1);
}
private static void DisplayCalendarInfo(System.Windows.Controls.TextBlock outputBlock, Calendar cal, DateTime date1)
{
outputBlock.Text += String.Format(" Calendar: {0}", GetCalendarName(cal)) + "\n";
outputBlock.Text += String.Format(" Era: {0}", cal.GetEra(date1)) + "\n";
outputBlock.Text += String.Format(" Year: {0}", cal.GetYear(date1)) + "\n";
outputBlock.Text += String.Format(" Month: {0}", cal.GetMonth(date1)) + "\n";
outputBlock.Text += String.Format(" DayOfYear: {0}", cal.GetDayOfYear(date1)) + "\n";
outputBlock.Text += String.Format(" DayOfMonth: {0}", cal.GetDayOfMonth(date1)) + "\n";
outputBlock.Text += String.Format(" DayOfWeek: {0}\n", cal.GetDayOfWeek(date1)) + "\n";
}
private static string GetCalendarName(Calendar cal)
{
return cal.ToString().Replace("System.Globalization.", "").
Replace("Calendar", "");
}
}
// The example displays the following output:
// April 3, 2011 in the Gregorian calendar is equivalent to:
// Calendar: UmAlQura
// Era: 1
// Year: 1432
// Month: 4
// DayOfYear: 118
// DayOfMonth: 29
// DayOfWeek: Sunday
//
// After adding 2 years and 10 months in the UmAlQura calendar,
// January 1, 2014 in the Gregorian calendar is equivalent to:
// Calendar: UmAlQura
// Era: 1
// Year: 1435
// Month: 2
// DayOfYear: 59
// DayOfMonth: 29
// DayOfWeek: Wednesday
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.
Change History
Date |
History |
Reason |
|---|---|---|
October 2010 |
Replaced the example. |
Customer feedback. |