DateTimeOffset.ToOffset(TimeSpan) 方法

定义

将当前 DateTimeOffset 对象的值转换为偏移值指定的日期和时间。

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

参数

offset
TimeSpan

要将值转换为的 DateTimeOffset 偏移量。

返回

一个对象,它等于原始 DateTimeOffset 对象(即,其 ToUniversalTime() 方法返回相同的时间点),但其 Offset 属性设置为 offset

例外

生成的 DateTimeOffset 对象的值 DateTime 早于 DateTimeOffset.MinValue

-或-

生成的 DateTimeOffset 对象的值 DateTime 晚于 DateTimeOffset.MaxValue

offset 小于 -14 小时。

-或-

offset 大于 14 小时。

示例

下面的示例演示如何使用ToOffset该方法将对象DateTimeOffset转换为DateTimeOffset具有不同偏移量的对象。

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

注解

该方法 ToOffset 是调用该方法的 TimeZoneInfo.ConvertTime(DateTimeOffset, TimeZoneInfo) 替代方法。 当已知时区与协调世界时(UTC)的偏移量时,执行从一个时区到另一个时区的简单转换非常有用。 但是,由于方法调用返回的原始 DateTimeOffset 对象和新 DateTimeOffset 对象都与特定时区无关,因此该方法不会在转换中应用任何时区调整规则。

适用于