DateTime.Kind 屬性
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。
取得值,指出這個執行個體表示的時間是根據本地時間、國際標準時間 (UTC),或兩者皆非。
public:
property DateTimeKind Kind { DateTimeKind get(); };
public DateTimeKind Kind { get; }
member this.Kind : DateTimeKind
Public ReadOnly Property Kind As DateTimeKind
屬性值
一個列舉值,表示目前時間表示的是什麼時間。 預設為 Unspecified。
範例
下列範例會使用 SpecifyKind 方法來示範 Kind 屬性如何影響 ToLocalTime 和 ToUniversalTime 轉換方法。
// This code example demonstrates the DateTime Kind, Now, and
// UtcNow properties, and the SpecifyKind(), ToLocalTime(),
// and ToUniversalTime() methods.
using System;
class Sample
{
public static void Main()
{
// Get the date and time for the current moment, adjusted
// to the local time zone.
DateTime saveNow = DateTime.Now;
// Get the date and time for the current moment expressed
// as coordinated universal time (UTC).
DateTime saveUtcNow = DateTime.UtcNow;
DateTime myDt;
// Display the value and Kind property of the current moment
// expressed as UTC and local time.
DisplayNow("UtcNow: ..........", saveUtcNow);
DisplayNow("Now: .............", saveNow);
Console.WriteLine();
// Change the Kind property of the current moment to
// DateTimeKind.Utc and display the result.
myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Utc);
Display("Utc: .............", myDt);
// Change the Kind property of the current moment to
// DateTimeKind.Local and display the result.
myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Local);
Display("Local: ...........", myDt);
// Change the Kind property of the current moment to
// DateTimeKind.Unspecified and display the result.
myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Unspecified);
Display("Unspecified: .....", myDt);
}
// Display the value and Kind property of a DateTime structure, the
// DateTime structure converted to local time, and the DateTime
// structure converted to universal time.
public static string datePatt = @"M/d/yyyy hh:mm:ss tt";
public static void Display(string title, DateTime inputDt)
{
DateTime dispDt = inputDt;
string dtString;
// Display the original DateTime.
dtString = dispDt.ToString(datePatt);
Console.WriteLine("{0} {1}, Kind = {2}",
title, dtString, dispDt.Kind);
// Convert inputDt to local time and display the result.
// If inputDt.Kind is DateTimeKind.Utc, the conversion is performed.
// If inputDt.Kind is DateTimeKind.Local, the conversion is not performed.
// If inputDt.Kind is DateTimeKind.Unspecified, the conversion is
// performed as if inputDt was universal time.
dispDt = inputDt.ToLocalTime();
dtString = dispDt.ToString(datePatt);
Console.WriteLine(" ToLocalTime: {0}, Kind = {1}",
dtString, dispDt.Kind);
// Convert inputDt to universal time and display the result.
// If inputDt.Kind is DateTimeKind.Utc, the conversion is not performed.
// If inputDt.Kind is DateTimeKind.Local, the conversion is performed.
// If inputDt.Kind is DateTimeKind.Unspecified, the conversion is
// performed as if inputDt was local time.
dispDt = inputDt.ToUniversalTime();
dtString = dispDt.ToString(datePatt);
Console.WriteLine(" ToUniversalTime: {0}, Kind = {1}",
dtString, dispDt.Kind);
Console.WriteLine();
}
// Display the value and Kind property for DateTime.Now and DateTime.UtcNow.
public static void DisplayNow(string title, DateTime inputDt)
{
string dtString = inputDt.ToString(datePatt);
Console.WriteLine("{0} {1}, Kind = {2}",
title, dtString, inputDt.Kind);
}
}
/*
This code example produces the following results:
UtcNow: .......... 5/6/2005 09:34:42 PM, Kind = Utc
Now: ............. 5/6/2005 02:34:42 PM, Kind = Local
Utc: ............. 5/6/2005 02:34:42 PM, Kind = Utc
ToLocalTime: 5/6/2005 07:34:42 AM, Kind = Local
ToUniversalTime: 5/6/2005 02:34:42 PM, Kind = Utc
Local: ........... 5/6/2005 02:34:42 PM, Kind = Local
ToLocalTime: 5/6/2005 02:34:42 PM, Kind = Local
ToUniversalTime: 5/6/2005 09:34:42 PM, Kind = Utc
Unspecified: ..... 5/6/2005 02:34:42 PM, Kind = Unspecified
ToLocalTime: 5/6/2005 07:34:42 AM, Kind = Local
ToUniversalTime: 5/6/2005 09:34:42 PM, Kind = Utc
*/
' This code example demonstrates the DateTime Kind, Now, and
' UtcNow properties, and the SpecifyKind(), ToLocalTime(),
' and ToUniversalTime() methods.
Class Sample
Public Shared Sub Main()
' Get the date and time for the current moment, adjusted
' to the local time zone.
Dim saveNow As DateTime = DateTime.Now
' Get the date and time for the current moment expressed
' as coordinated universal time (UTC).
Dim saveUtcNow As DateTime = DateTime.UtcNow
Dim myDt As DateTime
' Display the value and Kind property of the current moment
' expressed as UTC and local time.
DisplayNow("UtcNow: ..........", saveUtcNow)
DisplayNow("Now: .............", saveNow)
Console.WriteLine()
' Change the Kind property of the current moment to
' DateTimeKind.Utc and display the result.
myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Utc)
Display("Utc: .............", myDt)
' Change the Kind property of the current moment to
' DateTimeKind.Local and display the result.
myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Local)
Display("Local: ...........", myDt)
' Change the Kind property of the current moment to
' DateTimeKind.Unspecified and display the result.
myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Unspecified)
Display("Unspecified: .....", myDt)
End Sub
' Display the value and Kind property of a DateTime structure, the
' DateTime structure converted to local time, and the DateTime
' structure converted to universal time.
Public Shared datePatt As String = "M/d/yyyy hh:mm:ss tt"
Public Shared Sub Display(ByVal title As String, ByVal inputDt As DateTime)
Dim dispDt As DateTime = inputDt
Dim dtString As String
' Display the original DateTime.
dtString = dispDt.ToString(datePatt)
Console.WriteLine("{0} {1}, Kind = {2}", title, dtString, dispDt.Kind)
' Convert inputDt to local time and display the result.
' If inputDt.Kind is DateTimeKind.Utc, the conversion is performed.
' If inputDt.Kind is DateTimeKind.Local, the conversion is not performed.
' If inputDt.Kind is DateTimeKind.Unspecified, the conversion is
' performed as if inputDt was universal time.
dispDt = inputDt.ToLocalTime()
dtString = dispDt.ToString(datePatt)
Console.WriteLine(" ToLocalTime: {0}, Kind = {1}", dtString, dispDt.Kind)
' Convert inputDt to universal time and display the result.
' If inputDt.Kind is DateTimeKind.Utc, the conversion is not performed.
' If inputDt.Kind is DateTimeKind.Local, the conversion is performed.
' If inputDt.Kind is DateTimeKind.Unspecified, the conversion is
' performed as if inputDt was local time.
dispDt = inputDt.ToUniversalTime()
dtString = dispDt.ToString(datePatt)
Console.WriteLine(" ToUniversalTime: {0}, Kind = {1}", dtString, dispDt.Kind)
Console.WriteLine()
End Sub
' Display the value and Kind property for DateTime.Now and DateTime.UtcNow.
Public Shared Sub DisplayNow(ByVal title As String, ByVal inputDt As DateTime)
Dim dtString As String = inputDt.ToString(datePatt)
Console.WriteLine("{0} {1}, Kind = {2}", title, dtString, inputDt.Kind)
End Sub
End Class
'
'This code example produces the following results:
'
'UtcNow: .......... 5/6/2005 09:34:42 PM, Kind = Utc
'Now: ............. 5/6/2005 02:34:42 PM, Kind = Local
'
'Utc: ............. 5/6/2005 02:34:42 PM, Kind = Utc
' ToLocalTime: 5/6/2005 07:34:42 AM, Kind = Local
' ToUniversalTime: 5/6/2005 02:34:42 PM, Kind = Utc
'
'Local: ........... 5/6/2005 02:34:42 PM, Kind = Local
' ToLocalTime: 5/6/2005 02:34:42 PM, Kind = Local
' ToUniversalTime: 5/6/2005 09:34:42 PM, Kind = Utc
'
'Unspecified: ..... 5/6/2005 02:34:42 PM, Kind = Unspecified
' ToLocalTime: 5/6/2005 07:34:42 AM, Kind = Local
' ToUniversalTime: 5/6/2005 09:34:42 PM, Kind = Utc
'
備註
您可以藉 Kind 由呼叫方法,將新值的屬性明確設定 DateTime 為特定 DateTimeKind 值 SpecifyKind 。
Kind屬性可讓 DateTime 值清楚地反映國際標準時間 (UTC) 或本地時間。 相反地,此 DateTimeOffset 結構可以在任何時區中明確地反映單一時間點的任何時間。