DateTimeOffset.ToOffset(TimeSpan) 方法

定义

将当前 DateTimeOffset 对象的值转换为偏移量值所指定的日期和时间。

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

DateTimeOffset 值所转换成的偏移量。

返回

一个对象,它等于原始的 DateTimeOffset 对象(也就是说,它们的 ToUniversalTime() 方法返回的时间点相同),但其 Offset 属性设置为 offset

例外

生成的 DateTimeOffset 对象的 DateTime 值早于 DateTimeOffset.MinValue

\- 或 -

生成的 DateTimeOffset 对象的 DateTime 值晚于 DateTimeOffset.MaxValue

offset 小于 -14 小时。

- 或 -

offset 大于 14 小时。

示例

以下示例演示如何使用 ToOffset 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

方法 ToOffset 是调用 方法的 TimeZoneInfo.ConvertTime(DateTimeOffset, TimeZoneInfo) 替代方法。 当时区的偏移量与协调世界时 (UTC) 已知时,它可用于执行从一个时区到另一个时区的简单转换。 但是,由于方法调用返回的原始 DateTimeOffset 对象和新 DateTimeOffset 对象都与特定时区没有明确关联,因此该方法在转换中不应用任何时区调整规则。

适用于