DateTimeOffset.CompareTo(DateTimeOffset) 方法

定义

命名空间:

System

程序集:

System.Runtime.dll

Source:

DateTimeOffset.cs

将当前的 DateTimeOffset 对象与指定的 DateTimeOffset 对象进行比较，并指明当前对象是早于、等于还是晚于另一个 DateTimeOffset 对象。

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

参数

other

DateTimeOffset

将与当前的 DateTimeOffset 对象进行比较的对象。

返回

Int32

一个有符号的整数，它指明了当前的 DateTimeOffset 对象与 other 之间的关系，如下表所示。

返回值	说明
小于零	当前的 DateTimeOffset 对象早于 other。
零	当前的 DateTimeOffset 对象与 other 相同。
大于零。	当前的 DateTimeOffset 对象晚于 other。

实现

CompareTo(T)

示例

以下示例演示了对 CompareTo 方法的调用以比较 DateTimeOffset 对象。

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

注解

此方法通过比较对象的值来比较 DateTimeOffset 对象 UtcDateTime ;也就是说，它确定这两个对象是否表示单个时间点，并指示当前对象是早于、晚于还是与 参数相同 other 。