DateTimeOffset.ToString DateTimeOffset.ToString DateTimeOffset.ToString Method

Definition

Converts the value of the current DateTimeOffset object to its equivalent string representation.

Overloads

ToString() ToString() ToString()

Converts the value of the current DateTimeOffset object to its equivalent string representation.

ToString(IFormatProvider) ToString(IFormatProvider) ToString(IFormatProvider)

Converts the value of the current DateTimeOffset object to its equivalent string representation using the specified culture-specific formatting information.

ToString(String) ToString(String) ToString(String)

Converts the value of the current DateTimeOffset object to its equivalent string representation using the specified format.

ToString(String, IFormatProvider) ToString(String, IFormatProvider) ToString(String, IFormatProvider)

Converts the value of the current DateTimeOffset object to its equivalent string representation using the specified format and culture-specific format information.

ToString() ToString() ToString()

Converts the value of the current DateTimeOffset object to its equivalent string representation.

public:
 override System::String ^ ToString();
public override string ToString ();
Public Overrides Function ToString () As String
Returns

A string representation of a DateTimeOffset object that includes the offset appended at the end of the string.

Exceptions

The date and time is outside the range of dates supported by the calendar used by the current culture.

Examples

The following example illustrates calls to the ToString() method and displays its output on a system whose current culture is en-us.

DateTimeOffset thisDate;

// Show output for UTC time
thisDate = DateTimeOffset.UtcNow;
Console.WriteLine(thisDate.ToString());  // Displays 3/28/2007 7:13:50 PM +00:00

// Show output for local time 
thisDate = DateTimeOffset.Now;
Console.WriteLine(thisDate.ToString());  // Displays 3/28/2007 12:13:50 PM -07:00

// Show output for arbitrary time offset
thisDate = thisDate.ToOffset(new TimeSpan(-5, 0, 0));
Console.WriteLine(thisDate.ToString());  // Displays 3/28/2007 2:13:50 PM -05:00
Dim thisDate As DateTimeOffset

' Show output for UTC time
thisDate = DateTimeOffset.UtcNow
Console.WriteLine(thisDate.ToString())  ' Displays 3/28/2007 7:13:50 PM +00:00

' Show output for local time 
thisDate = DateTimeOffset.Now
Console.WriteLine(thisDate.ToString())  ' Displays 3/28/2007 12:13:50 PM -07:00

' Show output for arbitrary time offset
thisDate = thisDate.ToOffset(new TimeSpan(-5, 0, 0))
Console.WriteLine(thisDate.ToString())  ' Displays 3/28/2007 2:13:50 PM -05:00

Remarks

The return value of this method is identical to that of the DateTime.ToString() method, except that it includes a space followed by the offset appended at the end of the string. In other words, it formats output using the short date pattern, the long time pattern, and the zzz custom format string, with each element separated from the previous element by a space. For example, if DateTime.ToString() returns a value of 1/12/2008 6:15:50 PM, ToString() returns a value of 1/12/2008 6:15:50 PM -08:00 for a time that is eight hours behind Coordinated Universal Time (UTC).

This method uses formatting information derived from the current culture. For more information, see CurrentCulture. Other overloads of the ToString method enable you to specify the culture whose formatting to use, and to define the output pattern of the DateTimeOffset value.

Notes to Callers

The ToString() method returns the string representation of the date and time in the calendar used by the current culture. If the value of the current DateTimeOffset instance is earlier than MinSupportedDateTime or later than MaxSupportedDateTime, the method throws an ArgumentOutOfRangeException. The following example provides an illustration. It attempts to format a date that is outside the range of the HijriCalendar class when the current culture is Arabic (Syria).

using System;
using System.Globalization;
using System.Threading;

public class Example
{
   public static void Main()
   {
      DateTimeOffset date1 = new DateTimeOffset(new DateTime(550, 1, 1),
                                                TimeSpan.Zero);
      CultureInfo dft;
      CultureInfo arSY = new CultureInfo("ar-SY");
      arSY.DateTimeFormat.Calendar = new HijriCalendar();
      
      // Change current culture to ar-SY.
      dft = Thread.CurrentThread.CurrentCulture;
      Thread.CurrentThread.CurrentCulture = arSY;
      
      // Display the date using the current culture's calendar.            
      try {
         Console.WriteLine(date1.ToString());
      }
      catch (ArgumentOutOfRangeException) {
         Console.WriteLine("{0} is earlier than {1} or later than {2}", 
                           date1.ToString("d", CultureInfo.InvariantCulture), 
                           arSY.DateTimeFormat.Calendar.MinSupportedDateTime.ToString("d", CultureInfo.InvariantCulture),  
                           arSY.DateTimeFormat.Calendar.MaxSupportedDateTime.ToString("d", CultureInfo.InvariantCulture)); 
      }
      
      // Restore the default culture.
      Thread.CurrentThread.CurrentCulture = dft;
   }
}
// The example displays the following output:
//    01/01/0550 is earlier than 07/18/0622 or later than 12/31/9999
Imports System.Globalization
Imports System.Threading

Module Example
   Public Sub Main()
      Dim date1 As New DateTimeOffset(#1/1/550#, TimeSpan.Zero)
      Dim dft As CultureInfo
      Dim arSY As New CultureInfo("ar-SY")
      arSY.DateTimeFormat.Calendar = New HijriCalendar()
      
      ' Change current culture to ar-SY.
      dft = Thread.CurrentThread.CurrentCulture
      Thread.CurrentThread.CurrentCulture = arSY
      
      ' Display the date using the current culture's calendar.            
      Try
         Console.WriteLine(date1.ToString())
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine("{0} is earlier than {1:d} or later than {2:d}", _
                           date1.ToString("d", CultureInfo.InvariantCulture), _
                           arSY.DateTimeFormat.Calendar.MinSupportedDateTime.ToString("d", CultureInfo.InvariantCulture), _ 
                           arSY.DateTimeFormat.Calendar.MaxSupportedDateTime.ToString("d", CultureInfo.InvariantCulture)) 
      End Try
      
      ' Restore the default culture.
      Thread.CurrentThread.CurrentCulture = dft
   End Sub
End Module
' The example displays the following output:
'    01/01/0550 is earlier than 07/18/0622 or later than 12/31/9999

ToString(IFormatProvider) ToString(IFormatProvider) ToString(IFormatProvider)

Converts the value of the current DateTimeOffset object to its equivalent string representation using the specified culture-specific formatting information.

public:
 System::String ^ ToString(IFormatProvider ^ formatProvider);
public string ToString (IFormatProvider formatProvider);
Public Function ToString (formatProvider As IFormatProvider) As String
Parameters
formatProvider
IFormatProvider IFormatProvider IFormatProvider

An object that supplies culture-specific formatting information.

Returns

A string representation of the value of the current DateTimeOffset object, as specified by formatProvider.

Exceptions

The date and time is outside the range of dates supported by the calendar used by formatProvider.

Examples

The following example displays a DateTimeOffset object using CultureInfo objects that represent the invariant culture, as well as four other cultures.

CultureInfo[] cultures = new CultureInfo[] {CultureInfo.InvariantCulture, 
                                           new CultureInfo("en-us"), 
                                           new CultureInfo("fr-fr"), 
                                           new CultureInfo("de-DE"), 
                                           new CultureInfo("es-ES")};

DateTimeOffset thisDate = new DateTimeOffset(2007, 5, 1, 9, 0, 0, 
                                             TimeSpan.Zero);                                            

foreach (CultureInfo culture in cultures)
{
   string cultureName; 
   if (string.IsNullOrEmpty(culture.Name))
      cultureName = culture.NativeName;
   else
      cultureName = culture.Name;

   Console.WriteLine("In {0}, {1}", 
                     cultureName, thisDate.ToString(culture));
}                                            
// The example produces the following output:
//    In Invariant Language (Invariant Country), 05/01/2007 09:00:00 +00:00
//    In en-US, 5/1/2007 9:00:00 AM +00:00
//    In fr-FR, 01/05/2007 09:00:00 +00:00
//    In de-DE, 01.05.2007 09:00:00 +00:00
//    In es-ES, 01/05/2007 9:00:00 +00:00
Dim cultures() As CultureInfo = {CultureInfo.InvariantCulture, _
                                 New CultureInfo("en-us"), _
                                 New CultureInfo("fr-fr"), _
                                 New CultureInfo("de-DE"), _
                                 New CultureInfo("es-ES")}

Dim thisDate As New DateTimeOffset(#5/1/2007 9:00AM#, TimeSpan.Zero)                                            

For Each culture As CultureInfo In cultures
   Dim cultureName As String 
   If String.IsNullOrEmpty(culture.Name) Then
      cultureName = culture.NativeName
   Else
      cultureName = culture.Name
   End If
   Console.WriteLine("In {0}, {1}", _
                     cultureName, thisDate.ToString(culture))
Next                                            
' The example produces the following output:
'    In Invariant Language (Invariant Country), 05/01/2007 09:00:00 +00:00
'    In en-US, 5/1/2007 9:00:00 AM +00:00
'    In fr-FR, 01/05/2007 09:00:00 +00:00
'    In de-DE, 01.05.2007 09:00:00 +00:00
'    In es-ES, 01/05/2007 9:00:00 +00:00

Remarks

The return value of this method is identical to that of its equivalent overload of the DateTime.ToString method, except that it includes a space followed by the offset appended at the end of the string. In other words, it formats output using the short date pattern, the long time pattern, and the zzz custom format string, with each element separated from the previous element by a space.

The format of these three elements is defined by the formatProvider parameter. The formatProvider parameter can be either of the following:

If formatProvider is null, the DateTimeFormatInfo object associated with the current culture is used (see CurrentCulture).

Notes to Callers

The ToString(IFormatProvider) method returns the string representation of the date and time in the calendar used by the culture represented by the formatProvider parameter. Its calendar is defined by the Calendar property. If the value of the current DateTimeOffset instance is earlier than MinSupportedDateTime or later than MaxSupportedDateTime, the method throws an ArgumentOutOfRangeException. The following example provides an illustration. It attempts to format a date that is outside the range of the JapaneseCalendar class.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      CultureInfo jaJP = new CultureInfo("ja-JP");
      jaJP.DateTimeFormat.Calendar = new JapaneseCalendar(); 
      DateTimeOffset date1 = new DateTimeOffset(new DateTime(1867, 1, 1),
                                                TimeSpan.Zero);

      try {
         Console.WriteLine(date1.ToString(jaJP));
      }
      catch (ArgumentOutOfRangeException) {
         Console.WriteLine("{0:d} is earlier than {1:d} or later than {2:d}", 
                           date1, 
                           jaJP.DateTimeFormat.Calendar.MinSupportedDateTime,  
                           jaJP.DateTimeFormat.Calendar.MaxSupportedDateTime); 
      }
   }
}
// The example displays the following output:
//    1/1/1867 is earlier than 9/8/1868 or later than 12/31/9999   }
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim jaJP As New CultureInfo("ja-JP")
      jaJP.DateTimeFormat.Calendar = New JapaneseCalendar() 
      Dim date1 As New DateTimeOffset(#01/01/1867#, TimeSpan.Zero)

      Try
         Console.WriteLine(date1.ToString(jaJP))
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine("{0:d} is earlier than {1:d} or later than {2:d}", _
                           date1, _
                           jaJP.DateTimeFormat.Calendar.MinSupportedDateTime, _ 
                           jaJP.DateTimeFormat.Calendar.MaxSupportedDateTime) 
      End Try
   End Sub
End Module
' The example displays the following output:
'    1/1/1867 is earlier than 9/8/1868 or later than 12/31/9999

ToString(String) ToString(String) ToString(String)

Converts the value of the current DateTimeOffset object to its equivalent string representation using the specified format.

public:
 System::String ^ ToString(System::String ^ format);
public string ToString (string format);
Public Function ToString (format As String) As String
Parameters
format
String String String

A format string.

Returns

A string representation of the value of the current DateTimeOffset object, as specified by format.

Exceptions

The length of format is one, and it is not one of the standard format specifier characters defined for DateTimeFormatInfo.

-or-

format does not contain a valid custom format pattern.

The date and time is outside the range of dates supported by the calendar used by the current culture.

Examples

The following example displays a DateTimeOffset object to the console using each of the standard date and time format specifiers. The output is formatted by using the en-us culture.

DateTimeOffset outputDate = new DateTimeOffset(2007, 10, 31, 21, 0, 0, 
                                     new TimeSpan(-8, 0, 0));
string specifier; 
      
// Output date using each standard date/time format specifier
specifier = "d";
// Displays   d: 10/31/2007
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "D";
// Displays   D: Wednesday, October 31, 2007
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "t";
// Displays   t: 9:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "T";
// Displays   T: 9:00:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "f";
// Displays   f: Wednesday, October 31, 2007 9:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "F";
// Displays   F: Wednesday, October 31, 2007 9:00:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "g";
// Displays   g: 10/31/2007 9:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "G";
// Displays   G: 10/31/2007 9:00:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "M";           // 'm' is identical
// Displays   M: October 31
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "R";           // 'r' is identical
// Displays   R: Thu, 01 Nov 2007 05:00:00 GMT
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "s";
// Displays   s: 2007-10-31T21:00:00
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

specifier = "u";
// Displays   u: 2007-11-01 05:00:00Z
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 

// Specifier is not supported
specifier = "U";
try
{
   Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier));
}    
catch (FormatException)
{
   Console.WriteLine("{0}: Not supported.", specifier);   
}

specifier = "Y";         // 'y' is identical
// Displays   Y: October, 2007
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)); 
Dim outputDate As New DateTimeOffset(#10/31/2007 9:00PM#, _
                                     New TimeSpan(-8, 0, 0))
Dim specifier As String 
      
' Output date using each standard date/time format specifier
specifier = "d"
' Displays   d: 10/31/2007
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "D"
' Displays   D: Wednesday, October 31, 2007
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "t"
' Displays   t: 9:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "T"
' Displays   T: 9:00:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "f"
' Displays   f: Wednesday, October 31, 2007 9:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "F"
' Displays   F: Wednesday, October 31, 2007 9:00:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "g"
' Displays   g: 10/31/2007 9:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "G"
' Displays   G: 10/31/2007 9:00:00 PM
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "M"           ' 'm' is identical
' Displays   M: October 31
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "R"           ' 'r' is identical
' Displays   R: Thu, 01 Nov 2007 05:00:00 GMT
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "s"
' Displays   s: 2007-10-31T21:00:00
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

specifier = "u"
' Displays   u: 2007-11-01 05:00:00Z
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

' Specifier is not supported
specifier = "U"
Try
   Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 
Catch e As FormatException
   Console.WriteLine("{0}: Not supported.", specifier)   
End Try

specifier = "Y"         ' 'y' is identical
' Displays   Y: October, 2007
Console.WriteLine("{0}: {1}", specifier, outputDate.ToString(specifier)) 

Remarks

The format parameter should contain either a single format specifier character (see Standard Date and Time Format Strings) or a custom format pattern (see Custom Date and Time Format Strings) that defines the format of the returned string. If format is a null or empty string (""), the DateTimeOffset value is output using the default format.

The following table shows the exact operation of certain format specifiers when used with DateTimeOffset, which differs from their behavior when used with DateTime.

Existing format specifier New behavior
"K" Designed to round-trip a date and time. With DateTimeOffset, maps to "zzz" (the offset is always displayed with hours and minutes). Note that "K" is a custom format specifier; it cannot appear as the single character in format.
"U" Not supported.
"r" Converts the DateTimeOffset object to Coordinated Universal Time (UTC) and outputs it using the custom format string ddd, dd MMM yyyy HH:mm:ss GMT.
"u" Converts the DateTimeOffset object to UTC and outputs it using the format yyyy-MM-dd HH:mm:ssZ.

The remaining standard date and time format specifiers behave the same with the ToString(String) method as they do with the ToString method.

This method uses formatting information derived from the current culture. For more information, see CurrentCulture.

Notes to Callers

The ToString(String) method returns the string representation of the date and time in the calendar used by the current culture. If the value of the current DateTimeOffset instance is earlier than MinSupportedDateTime or later than MaxSupportedDateTime, the method throws an ArgumentOutOfRangeException. The following example provides an illustration. It attempts to format a date that is outside the range of the HebrewCalendar class when the current culture is Hebrew (Israel).

using System;
using System.Globalization;
using System.Threading;

public class Example
{
   public static void Main()
   {
      DateTimeOffset date1 = new DateTimeOffset(new DateTime(1550, 7, 21),
                                                TimeSpan.Zero);
      CultureInfo dft;
      CultureInfo heIL = new CultureInfo("he-IL");
      heIL.DateTimeFormat.Calendar = new HebrewCalendar();
      
      // Change current culture to he-IL.
      dft = Thread.CurrentThread.CurrentCulture;
      Thread.CurrentThread.CurrentCulture = heIL;
      
      // Display the date using the current culture's calendar.            
      try {
         Console.WriteLine(date1.ToString("G"));
      }   
      catch (ArgumentOutOfRangeException) {
         Console.WriteLine("{0} is earlier than {1} or later than {2}", 
                           date1.ToString("d", CultureInfo.InvariantCulture), 
                           heIL.DateTimeFormat.Calendar.MinSupportedDateTime.ToString("d", CultureInfo.InvariantCulture),  
                           heIL.DateTimeFormat.Calendar.MaxSupportedDateTime.ToString("d", CultureInfo.InvariantCulture)); 
      }
      
      // Restore the default culture.
      Thread.CurrentThread.CurrentCulture = dft;
   }
}
// The example displays the following output:
//    07/21/1550 is earlier than 01/01/1583 or later than 09/29/2239
Imports System.Globalization
Imports System.Threading

Module Example
   Public Sub Main()
      Dim date1 As New DateTimeOffset(#7/21/1550#, TimeSpan.Zero)
      Dim dft As CultureInfo
      Dim heIL As New CultureInfo("he-IL")
      heIL.DateTimeFormat.Calendar = New HebrewCalendar()
      
      ' Change current culture to he-IL.
      dft = Thread.CurrentThread.CurrentCulture
      Thread.CurrentThread.CurrentCulture = heIL
      
      ' Display the date using the current culture's calendar.            
      Try
         Console.WriteLine(date1.ToString("G"))
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine("{0} is earlier than {1} or later than {2}", _
                           date1.ToString("d", CultureInfo.InvariantCulture), _
                           heIL.DateTimeFormat.Calendar.MinSupportedDateTime.ToString("d", CultureInfo.InvariantCulture), _ 
                           heIL.DateTimeFormat.Calendar.MaxSupportedDateTime.ToString("d", CultureInfo.InvariantCulture)) 
      End Try
      
      ' Restore the default culture.
      Thread.CurrentThread.CurrentCulture = dft
   End Sub
End Module
' The example displays the following output:
'    07/21/1550 is earlier than 01/01/1583 or later than 09/29/2239

ToString(String, IFormatProvider) ToString(String, IFormatProvider) ToString(String, IFormatProvider)

Converts the value of the current DateTimeOffset object to its equivalent string representation using the specified format and culture-specific format information.

public:
 virtual System::String ^ ToString(System::String ^ format, IFormatProvider ^ formatProvider);
public string ToString (string format, IFormatProvider formatProvider);
Public Function ToString (format As String, formatProvider As IFormatProvider) As String
Parameters
format
String String String

A format string.

formatProvider
IFormatProvider IFormatProvider IFormatProvider

An object that supplies culture-specific formatting information.

Returns

A string representation of the value of the current DateTimeOffset object, as specified by format and provider.

Implements
Exceptions

The length of format is one, and it is not one of the standard format specifier characters defined for DateTimeFormatInfo.

-or-

format does not contain a valid custom format pattern.

The date and time is outside the range of dates supported by the calendar used by formatProvider.

Examples

The following example uses the ToString(String, IFormatProvider) method to display a DateTimeOffset object using a custom format string for several different cultures.

DateTimeOffset outputDate = new DateTimeOffset(2007, 11, 1, 9, 0, 0, 
                                     new TimeSpan(-7, 0, 0)); 
string format = "dddd, MMM dd yyyy HH:mm:ss zzz";

// Output date and time using custom format specification
Console.WriteLine(outputDate.ToString(format, null as DateTimeFormatInfo));
Console.WriteLine(outputDate.ToString(format, CultureInfo.InvariantCulture));
Console.WriteLine(outputDate.ToString(format, 
                                      new CultureInfo("fr-FR")));
Console.WriteLine(outputDate.ToString(format, 
                                      new CultureInfo("es-ES")));
// The example displays the following output to the console:
//    Thursday, Nov 01 2007 09:00:00 -07:00
//    Thursday, Nov 01 2007 09:00:00 -07:00
//    jeudi, nov. 01 2007 09:00:00 -07:00
//    jueves, nov 01 2007 09:00:00 -07:00
Dim outputDate As New DateTimeOffset(#11/1/2007 9:00AM#, _
                                     New TimeSpan(-7, 0, 0)) 
Dim format As String = "dddd, MMM dd yyyy HH:mm:ss zzz"

' Output date and time using custom format specification
Console.WriteLine(outputDate.ToString(format, Nothing))
Console.WriteLine(outputDate.ToString(format, CultureInfo.InvariantCulture))
Console.WriteLine(outputDate.ToString(format, _
                                      New CultureInfo("fr-FR")))
Console.WriteLine(outputDate.ToString(format, _
                                      New CultureInfo("es-ES")))
' The example displays the following output to the console:
'    Thursday, Nov 01 2007 09:00:00 -07:00
'    Thursday, Nov 01 2007 09:00:00 -07:00
'    jeudi, nov. 01 2007 09:00:00 -07:00
'    jueves, nov 01 2007 09:00:00 -07:00

Remarks

The format parameter should contain either a single format specifier character (see Standard Date and Time Format Strings) or a custom format pattern (see Custom Date and Time Format Strings). If format is a null or empty string (""), the DateTimeOffset object is output using the default format.

The following table shows the exact operation of certain format specifiers when used with DateTimeOffset, which differs from their behavior when used with DateTime.

Existing format specifier New behavior
"K" Designed to round-trip a date and time. With DateTimeOffset, maps to "zzz" (the offset is always displayed with hours and minutes). Note that "K" is a custom format specifier; it cannot appear as the single character in format.
"U" Not supported.
"r" Converts the DateTimeOffset object to Coordinated Universal Time (UTC) and outputs it using the custom format string ddd, dd MMM yyyy HH:mm:ss GMT.
"u" Converts the DateTimeOffset value to UTC and outputs it using the format yyyy-MM-dd HH:mm:ssZ.

The remaining standard date and time format specifiers behave the same with the ToString(String) method as they do with the ToString method.

The pattern that corresponds to standard format specifiers, as well as the symbols and names of date and time components, is defined by the formatProvider parameter. The formatProvider parameter can be either of the following:

If formatProvider is null, the DateTimeFormatInfo object associated with the current culture is used (see CurrentCulture).

Notes to Callers

The ToString(String, IFormatProvider) method returns the string representation of the date and time in the calendar used by the formatProvider parameter. Its calendar is defined by the Calendar property. If the value of the current DateTimeOffset instance is earlier than MinSupportedDateTime or later than MaxSupportedDateTime, the method throws an ArgumentOutOfRangeException. The following example provides an illustration. It attempts to format a date that is outside the range of the UmAlQuraCalendar class.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      CultureInfo arSA = new CultureInfo("ar-SA");
      arSA.DateTimeFormat.Calendar = new UmAlQuraCalendar(); 
      DateTimeOffset date1 = new DateTimeOffset(new DateTime(1890, 9, 10),
                                                TimeSpan.Zero);

      try {
         Console.WriteLine(date1.ToString("d", arSA));
      }   
      catch (ArgumentOutOfRangeException) {
         Console.WriteLine("{0:d} is earlier than {1:d} or later than {2:d}", 
                           date1, 
                           arSA.DateTimeFormat.Calendar.MinSupportedDateTime,  
                           arSA.DateTimeFormat.Calendar.MaxSupportedDateTime); 
      }
   }
}
// The example displays the following output:
//    9/10/1890 is earlier than 4/30/1900 or later than 5/13/2029
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim arSA As New CultureInfo("ar-SA")
      arSA.DateTimeFormat.Calendar = New UmAlQuraCalendar() 
      Dim date1 As New DateTimeOffset(#09/10/1890#, TimeSpan.Zero)

      Try
         Console.WriteLine(date1.ToString("d", arSA))
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine("{0:d} is earlier than {1:d} or later than {2:d}", _
                           date1, _
                           arSA.DateTimeFormat.Calendar.MinSupportedDateTime, _ 
                           arSA.DateTimeFormat.Calendar.MaxSupportedDateTime) 
      End Try
   End Sub
End Module
' The example displays the following output:
'    9/10/1890 is earlier than 4/30/1900 or later than 5/13/2029

Applies to