DateTimeOffset.ToOffset(TimeSpan) 方法

定義

將當前 DateTimeOffset 物件的值轉換為由偏移值指定的日期與時間。

public:
 DateTimeOffset ToOffset(TimeSpan offset);
public DateTimeOffset ToOffset(TimeSpan offset);
member this.ToOffset : TimeSpan -> DateTimeOffset
Public Function ToOffset (offset As TimeSpan) As DateTimeOffset

參數

offset
TimeSpan

將該值轉換為 DateTimeOffset 的偏移量。

傳回

一個等於原始 DateTimeOffset 物件的物件(也就是說,它們 ToUniversalTime() 的方法回傳相同的時間點),但其 Offset 屬性被設定為 offset

例外狀況

所得 DateTimeOffset 物件的 DateTime 值早於 DateTimeOffset.MinValue

-或-

所得物件 DateTimeOffsetDateTime 值晚於 DateTimeOffset.MaxValue

offset 不到 -14 小時。

-或-

offset 超過14小時。

範例

以下範例說明如何使用此 ToOffset 方法將物件 DateTimeOffset 轉換成 DateTimeOffset 偏移量不同的物件。

using System;

public class DateTimeOffsetConversion
{
   private static DateTimeOffset sourceTime;

   public static void Main()
   {
      DateTimeOffset targetTime;
      sourceTime = new DateTimeOffset(2007, 9, 1, 9, 30, 0,
                                      new TimeSpan(-5, 0, 0));

      // Convert to same time (return sourceTime unchanged)
      targetTime = sourceTime.ToOffset(new TimeSpan(-5, 0, 0));
      ShowDateAndTimeInfo(targetTime);

      // Convert to UTC (0 offset)
      targetTime = sourceTime.ToOffset(TimeSpan.Zero);
      ShowDateAndTimeInfo(targetTime);

      // Convert to 8 hours behind UTC
      targetTime = sourceTime.ToOffset(new TimeSpan(-8, 0, 0));
      ShowDateAndTimeInfo(targetTime);

      // Convert to 3 hours ahead of UTC
      targetTime = sourceTime.ToOffset(new TimeSpan(3, 0, 0));
      ShowDateAndTimeInfo(targetTime);
   }

   private static void ShowDateAndTimeInfo(DateTimeOffset newTime)
   {
      Console.WriteLine("{0} converts to {1}", sourceTime, newTime);
      Console.WriteLine("{0} and {1} are equal: {2}",
                        sourceTime, newTime, sourceTime.Equals(newTime));
      Console.WriteLine("{0} and {1} are identical: {2}",
                        sourceTime, newTime,
                        sourceTime.EqualsExact(newTime));
      Console.WriteLine();
   }
}
//
// The example displays the following output:
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 9:30:00 AM -05:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 9:30:00 AM -05:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 9:30:00 AM -05:00 are identical: True
//
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 2:30:00 PM +00:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 2:30:00 PM +00:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 2:30:00 PM +00:00 are identical: False
//
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 6:30:00 AM -08:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 6:30:00 AM -08:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 6:30:00 AM -08:00 are identical: False
//
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 5:30:00 PM +03:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 5:30:00 PM +03:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 5:30:00 PM +03:00 are identical: False
open System

let sourceTime = DateTimeOffset(2007, 9, 1, 9, 30, 0, TimeSpan(-5, 0, 0))

let showDateAndTimeInfo newTime =
    printfn $"{sourceTime} converts to {newTime}"
    printfn $"{sourceTime} and {newTime} are equal: {sourceTime.Equals newTime}"
    printfn $"{sourceTime} and {newTime} are identical: {sourceTime.EqualsExact newTime}\n"

[<EntryPoint>]
let main _ =
    // Convert to same time (return sourceTime unchanged)
    let targetTime = sourceTime.ToOffset(TimeSpan(-5, 0, 0))
    showDateAndTimeInfo targetTime

    // Convert to UTC (0 offset)
    let targetTime = sourceTime.ToOffset TimeSpan.Zero
    showDateAndTimeInfo targetTime

    // Convert to 8 hours behind UTC
    let targetTime = sourceTime.ToOffset(TimeSpan(-8, 0, 0))
    showDateAndTimeInfo targetTime

    // Convert to 3 hours ahead of UTC
    let targetTime = sourceTime.ToOffset(TimeSpan(3, 0, 0))
    showDateAndTimeInfo targetTime

    0

// The example displays the following output:
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 9:30:00 AM -05:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 9:30:00 AM -05:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 9:30:00 AM -05:00 are identical: True
//
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 2:30:00 PM +00:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 2:30:00 PM +00:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 2:30:00 PM +00:00 are identical: False
//
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 6:30:00 AM -08:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 6:30:00 AM -08:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 6:30:00 AM -08:00 are identical: False
//
//    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 5:30:00 PM +03:00
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 5:30:00 PM +03:00 are equal: True
//    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 5:30:00 PM +03:00 are identical: False
Module DateTimeOffsetConversion
   Private sourceTime As New DateTimeOffset(#9/1/2007 9:30AM#, _
                                            New TimeSpan(-5, 0, 0))
   
   Public Sub Main()
      Dim targetTime As DateTimeOffset
      
      ' Convert to same time (return sourceTime unchanged)
      targetTime = sourceTime.ToOffset(New TimeSpan(-5, 0, 0))
      ShowDateAndTimeInfo(targetTime)
      
      ' Convert to UTC (0 offset)
      targetTime = sourceTime.ToOffset(TimeSpan.Zero)
      ShowDateAndTimeInfo(targetTime)
      
      ' Convert to 8 hours behind UTC
      targetTime = sourceTime.ToOffset(New TimeSpan(-8, 0, 0))
      ShowDateAndTimeInfo(targetTime)
      
      ' Convert to 3 hours ahead of UTC
      targetTime = sourceTime.ToOffset(New TimeSpan(3, 0, 0))
      ShowDateAndTimeInfo(targetTime)
   End Sub
   
   Private Sub ShowDateAndTimeInfo(newTime As DateTimeOffset)
      Console.WriteLine("{0} converts to {1}", sourceTime, newTime)
      Console.WriteLine("{0} and {1} are equal: {2}", _
                        sourceTime, newTime, sourceTime.Equals(newTime))
      Console.WriteLine("{0} and {1} are identical: {2}", _
                        sourceTime, newTime, _
                        sourceTime.EqualsExact(newTime)) 
      Console.WriteLine()
   End Sub
End Module
'
' The example displays the following output:
'    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 9:30:00 AM -05:00
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 9:30:00 AM -05:00 are equal: True
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 9:30:00 AM -05:00 are identical: True
'    
'    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 2:30:00 PM +00:00
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 2:30:00 PM +00:00 are equal: True
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 2:30:00 PM +00:00 are identical: False
'    
'    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 6:30:00 AM -08:00
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 6:30:00 AM -08:00 are equal: True
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 6:30:00 AM -08:00 are identical: False
'    
'    9/1/2007 9:30:00 AM -05:00 converts to 9/1/2007 5:30:00 PM +03:00
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 5:30:00 PM +03:00 are equal: True
'    9/1/2007 9:30:00 AM -05:00 and 9/1/2007 5:30:00 PM +03:00 are identical: False

備註

ToOffset 方法是呼叫 TimeZoneInfo.ConvertTime(DateTimeOffset, TimeZoneInfo) 方法的替代方案。 當已知時區與協調世界時(UTC)的偏移時,它對於執行從一個時區到另一個時區的簡單換算非常有用。 然而,由於原始 DateTimeOffset 物件與 DateTimeOffset 新物件皆不明確關聯特定時區,該方法在轉換時不套用任何時區調整規則。

適用於