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DateTimeOffset.CompareTo(DateTimeOffset) Method

Definition

Compares the current DateTimeOffset object to a specified DateTimeOffset object and indicates whether the current object is earlier than, the same as, or later than the second DateTimeOffset object.

public:
 virtual int CompareTo(DateTimeOffset other);
public int CompareTo (DateTimeOffset other);
abstract member CompareTo : DateTimeOffset -> int
override this.CompareTo : DateTimeOffset -> int
Public Function CompareTo (other As DateTimeOffset) As Integer

Parameters

other
DateTimeOffset

An object to compare with the current DateTimeOffset object.

Returns

A signed integer that indicates the relationship between the current DateTimeOffset object and other, as the following table shows.

Return Value Description
Less than zero The current DateTimeOffset object is earlier than other.
Zero The current DateTimeOffset object is the same as other.
Greater than zero. The current DateTimeOffset object is later than other.

Implements

Examples

The following example illustrates calls to the CompareTo method to compare DateTimeOffset objects.

using System;

public class CompareTimes
{
   private enum TimeComparison
   {
      Earlier = -1,
      Same = 0,
      Later = 1
   };

   public static void Main()
   {
      DateTimeOffset firstTime = new DateTimeOffset(2007, 9, 1, 6, 45, 0,
                                 new TimeSpan(-7, 0, 0));

      DateTimeOffset secondTime = firstTime;
      Console.WriteLine("Comparing {0} and {1}: {2}",
                        firstTime, secondTime,
                        (TimeComparison) firstTime.CompareTo(secondTime));

      secondTime = new DateTimeOffset(2007, 9, 1, 6, 45, 0,
                       new TimeSpan(-6, 0, 0));
      Console.WriteLine("Comparing {0} and {1}: {2}",
                       firstTime, secondTime,
                       (TimeComparison) firstTime.CompareTo(secondTime));

      secondTime = new DateTimeOffset(2007, 9, 1, 8, 45, 0,
                       new TimeSpan(-5, 0, 0));
      Console.WriteLine("Comparing {0} and {1}: {2}",
                       firstTime, secondTime,
                       (TimeComparison) firstTime.CompareTo(secondTime));
      // The example displays the following output to the console:
      //       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 6:45:00 AM -07:00: Same
      //       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 6:45:00 AM -06:00: Later
      //       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 8:45:00 AM -05:00: Same
   }
}
open System

type TimeComparison =
    | Earlier = -1
    | Same = 0
    | Later = 1

let firstTime = DateTimeOffset(2007, 9, 1, 6, 45, 0, TimeSpan(-7, 0, 0))

let secondTime = firstTime
printfn $"Comparing {firstTime} and {secondTime}: {firstTime.CompareTo secondTime |> enum<TimeComparison>}"

let thirdTime = DateTimeOffset(2007, 9, 1, 6, 45, 0, TimeSpan(-6, 0, 0))
printfn $"Comparing {firstTime} and {thirdTime}: {firstTime.CompareTo thirdTime |> enum<TimeComparison>}"

let fourthTime = new DateTimeOffset(2007, 9, 1, 8, 45, 0,
                new TimeSpan(-5, 0, 0))
printfn $"Comparing {firstTime} and {fourthTime}: {firstTime.CompareTo fourthTime |> enum<TimeComparison>}" 
                
// The example displays the following output to the console:
//       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 6:45:00 AM -07:00: Same
//       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 6:45:00 AM -06:00: Later
//       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 8:45:00 AM -05:00: Same
Module CompareTimes
   Private Enum TimeComparison As Integer
      Earlier = -1
      Same = 0
      Later = 1
   End Enum
      
   Public Sub Main()
      Dim firstTime As New DateTimeOffset(#09/01/2007 6:45:00AM#, _
                       New TimeSpan(-7, 0, 0))
  
      Dim secondTime As DateTimeOffset = firstTime
      Console.WriteLine("Comparing {0} and {1}: {2}", _
                        firstTime, secondTime, _
                        CType(firstTime.CompareTo(secondTime), _
                              TimeComparison))

      secondTime = New DateTimeOffset(#09/01/2007 6:45:00AM#, _
                       New TimeSpan(-6, 0, 0))      
      Console.WriteLine("Comparing {0} and {1}: {2}", _
                       firstTime, secondTime, _
                       CType(firstTime.CompareTo(secondTime), _
                             TimeComparison))
      
      secondTime = New DateTimeOffset(#09/01/2007 8:45:00AM#, _
                       New TimeSpan(-5, 0, 0))
      Console.WriteLine("Comparing {0} and {1}: {2}", _
                       firstTime, secondTime, _
                       CType(firstTime.CompareTo(secondTime), _
                             TimeComparison))
      ' The example displays the following output to the console:
      '       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 6:45:00 AM -07:00: Same
      '       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 6:45:00 AM -06:00: Later
      '       Comparing 9/1/2007 6:45:00 AM -07:00 and 9/1/2007 8:45:00 AM -05:00: Same      
   End Sub
End Module

Remarks

This method compares DateTimeOffset objects by comparing their UtcDateTime values; that is, it determines whether the two objects represent a single point in time, and indicates whether the current object is earlier than, later than, or the same as the other parameter.

Applies to