DateTimeOffset.Compare(DateTimeOffset, DateTimeOffset) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
比較兩個 DateTimeOffset 物件,並指出第一個日期是早於、等於還是晚於第二個日期。
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
要比較的第一個物件。
- second
- DateTimeOffset
要比較的第二個物件。
傳回
帶正負號的整數,表示 first
參數的值是早於、晚於或等於 second
參數的值,如下表所示。
傳回值 | 意義 |
---|---|
小於零 | first 早於 second 。
|
零 | first 等於 second 。
|
大於零 | first 晚於 second 。
|
範例
下列範例說明對 方法的 Compare 呼叫,以比較 DateTimeOffset 物件。
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
在執行比較時,方法會將 和 second
參數轉換成 first
國際標準時間 (UTC) ,然後再執行比較。 方法相當於下列專案:
return DateTime.Compare(first.UtcDateTime, second.UtcDateTime);
DateTime.Compare(first.UtcDateTime, second.UtcDateTime)
Return DateTime.Compare(first.UtcDateTime, second.UtcDateTime)
換句話說, Compare 方法會判斷兩 DateTimeOffset 個 物件是否代表單一時間點。 它會直接比較日期和時間和位移。