DateTimeOffset.Compare(DateTimeOffset, DateTimeOffset) 方法

定義

比較兩個 DateTimeOffset 物體,並表示第一個物體是比第二個更早、等於第二個,還是比第二個更晚。

public:
 static int Compare(DateTimeOffset first, DateTimeOffset second);
public static int Compare(DateTimeOffset first, DateTimeOffset second);
static member Compare : DateTimeOffset * DateTimeOffset -> int
Public Shared Function Compare (first As DateTimeOffset, second As DateTimeOffset) As Integer

參數

first
DateTimeOffset

第一個比較的對象。

second
DateTimeOffset

第二個比較物件。

傳回

一個帶符號整數,表示參數值 first 是早於、晚於或同時 second ,如下表所示。

回傳價值 意義
低於零 first比 早。second
first 等於 second
大於零 first比 晚。second

範例

以下範例說明了比較物件的方法呼叫CompareDateTimeOffset

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) DateTimeOffset.Compare(firstTime, 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) DateTimeOffset.Compare(firstTime, 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) DateTimeOffset.Compare(firstTime, 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}: {DateTimeOffset.Compare(firstTime, secondTime) |> enum<TimeComparison>}"

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

let fourthTime = DateTimeOffset(2007, 9, 1, 8, 45, 0, TimeSpan(-5, 0, 0))
printfn $"Comparing {firstTime} and {fourthTime}: {DateTimeOffset.Compare(firstTime, 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(DateTimeOffset.Compare(firstTime, 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(DateTimeOffset.Compare(firstTime, 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(DateTimeOffset.Compare(firstTime, 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

備註

在進行比較時,方法會先將 與 first 參數 second 都轉換為協調世界時(UTC),再進行比較。 此方法等同於以下方法:

return DateTime.Compare(first.UtcDateTime, second.UtcDateTime);
DateTime.Compare(first.UtcDateTime, second.UtcDateTime)
Return DateTime.Compare(first.UtcDateTime, second.UtcDateTime)

換句話說,該 Compare 方法判斷兩個 DateTimeOffset 物體是否代表同一時間點。 它既不直接比較日期、時間,也不比對偏移量。

適用於