Directory.GetLastAccessTimeUtc(String) Méthode
Définition
Important
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Retourne la date et l’heure, au format UTC (Temps universel coordonné), auquel le fichier ou répertoire spécifié a été consulté pour la dernière fois.
public:
static DateTime GetLastAccessTimeUtc(System::String ^ path);
public static DateTime GetLastAccessTimeUtc(string path);
static member GetLastAccessTimeUtc : string -> DateTime
Public Shared Function GetLastAccessTimeUtc (path As String) As DateTime
Paramètres
- path
- String
Fichier ou répertoire pour lequel obtenir des informations de date et d’heure d’accès.
Retours
Structure définie sur la date et l’heure auxquelles le fichier ou répertoire spécifié a été accédé pour la dernière fois. Cette valeur est exprimée en heure UTC.
Exceptions
L’appelant n’a pas l’autorisation requise.
.NET Framework et les versions .NET Core antérieures à 2.1 : path est une chaîne de longueur nulle, contient uniquement un espace blanc ou contient un ou plusieurs caractères non valides. Vous pouvez rechercher des caractères non valides avec la GetInvalidPathChars() méthode.
path a la valeur null.
Le chemin d’accès spécifié, le nom de fichier ou les deux dépassent la longueur maximale définie par le système.
Le path paramètre est dans un format non valide.
Exemples
L’exemple suivant illustre les différences de sortie lors de l’utilisation de la sortie UTC (Temps universel coordonné).
// This sample shows the differences between dates from methods that use
//coordinated universal time (UTC) format and those that do not.
using System;
using System.IO;
namespace IOSamples
{
public class DirectoryUTCTime
{
public static void Main()
{
// Set the directory.
string n = @"C:\test\newdir";
//Create two variables to use to set the time.
DateTime dtime1 = new DateTime(2002, 1, 3);
DateTime dtime2 = new DateTime(1999, 1, 1);
//Create the directory.
try
{
Directory.CreateDirectory(n);
}
catch (IOException e)
{
Console.WriteLine(e);
}
//Set the creation and last access times to a variable DateTime value.
Directory.SetCreationTime(n, dtime1);
Directory.SetLastAccessTimeUtc(n, dtime1);
// Print to console the results.
Console.WriteLine("Creation Date: {0}", Directory.GetCreationTime(n));
Console.WriteLine("UTC creation Date: {0}", Directory.GetCreationTimeUtc(n));
Console.WriteLine("Last write time: {0}", Directory.GetLastWriteTime(n));
Console.WriteLine("UTC last write time: {0}", Directory.GetLastWriteTimeUtc(n));
Console.WriteLine("Last access time: {0}", Directory.GetLastAccessTime(n));
Console.WriteLine("UTC last access time: {0}", Directory.GetLastAccessTimeUtc(n));
//Set the last write time to a different value.
Directory.SetLastWriteTimeUtc(n, dtime2);
Console.WriteLine("Changed last write time: {0}", Directory.GetLastWriteTimeUtc(n));
}
}
}
// Obviously, since this sample deals with dates and times, the output will vary
// depending on when you run the executable. Here is one example of the output:
//Creation Date: 1/3/2002 12:00:00 AM
//UTC creation Date: 1/3/2002 8:00:00 AM
//Last write time: 12/31/1998 4:00:00 PM
//UTC last write time: 1/1/1999 12:00:00 AM
//Last access time: 1/2/2002 4:00:00 PM
//UTC last access time: 1/3/2002 12:00:00 AM
//Changed last write time: 1/1/1999 12:00:00 AM
// This sample shows the differences between dates from methods that use
//coordinated universal time (UTC) format and those that do not.
open System
open System.IO
// Set the directory.
let n = @"C:\test\newdir"
//Create two variables to use to set the time.
let dtime1 = DateTime(2002, 1, 3)
let dtime2 = DateTime(1999, 1, 1)
//Create the directory.
try
Directory.CreateDirectory n |> ignore
with :? IOException as e ->
printfn $"{e}"
//Set the creation and last access times to a variable DateTime value.
Directory.SetCreationTime(n, dtime1)
Directory.SetLastAccessTimeUtc(n, dtime1)
// Print to console the results.
printfn $"Creation Date: {Directory.GetCreationTime n}"
printfn $"UTC creation Date: {Directory.GetCreationTimeUtc n}"
printfn $"Last write time: {Directory.GetLastWriteTime n}"
printfn $"UTC last write time: {Directory.GetLastWriteTimeUtc n}"
printfn $"Last access time: {Directory.GetLastAccessTime n}"
printfn $"UTC last access time: {Directory.GetLastAccessTimeUtc n}"
//Set the last write time to a different value.
Directory.SetLastWriteTimeUtc(n, dtime2)
printfn $"Changed last write time: {Directory.GetLastWriteTimeUtc n}"
// Obviously, since this sample deals with dates and times, the output will vary
// depending on when you run the executable. Here is one example of the output:
//Creation Date: 1/3/2002 12:00:00 AM
//UTC creation Date: 1/3/2002 8:00:00 AM
//Last write time: 12/31/1998 4:00:00 PM
//UTC last write time: 1/1/1999 12:00:00 AM
//Last access time: 1/2/2002 4:00:00 PM
//UTC last access time: 1/3/2002 12:00:00 AM
//Changed last write time: 1/1/1999 12:00:00 AM
' This sample shows the differences between dates from methods that use
'coordinated universal time (UTC) format and those that do not.
Imports System.IO
Public Class DirectoryUTCTime
Public Shared Sub Main()
' Set the directory.
Dim n As String = "C:\test\newdir"
'Create two variables to use to set the time.
Dim dtime1 As New DateTime(2002, 1, 3)
Dim dtime2 As New DateTime(1999, 1, 1)
'Create the directory.
Try
Directory.CreateDirectory(n)
Catch e As IOException
Console.WriteLine(e)
End Try
'Set the creation and last access times to a variable DateTime value.
Directory.SetCreationTime(n, dtime1)
Directory.SetLastAccessTimeUtc(n, dtime1)
' Print to console the results.
Console.WriteLine("Creation Date: {0}", Directory.GetCreationTime(n))
Console.WriteLine("UTC creation Date: {0}", Directory.GetCreationTimeUtc(n))
Console.WriteLine("Last write time: {0}", Directory.GetLastWriteTime(n))
Console.WriteLine("UTC last write time: {0}", Directory.GetLastWriteTimeUtc(n))
Console.WriteLine("Last access time: {0}", Directory.GetLastAccessTime(n))
Console.WriteLine("UTC last access time: {0}", Directory.GetLastAccessTimeUtc(n))
'Set the last write time to a different value.
Directory.SetLastWriteTimeUtc(n, dtime2)
Console.WriteLine("Changed last write time: {0}", Directory.GetLastWriteTimeUtc(n))
End Sub
End Class
' Since this sample deals with dates and times, the output will vary
' depending on when you run the executable. Here is one example of the output:
' Creation Date: 1/3/2002 12:00:00 AM
' UTC creation Date: 1/3/2002 8:00:00 AM
' Last write time: 12/31/1998 4:00:00 PM
' UTC last write time: 1/1/1999 12:00:00 AM
' Last access time: 1/2/2002 4:00:00 PM
' UTC last access time: 1/3/2002 12:00:00 AM
' Changed last write time: 1/1/1999 12:00:00 AM
Remarques
Note
Cette méthode peut retourner une valeur inexacte, car elle utilise des fonctions natives dont les valeurs peuvent ne pas être mises à jour en continu par le système d’exploitation.
Si le répertoire décrit dans le path paramètre n’existe pas, cette méthode retourne 12:00 minuit, le 1er janvier 1601 A.D. (C.E.) Temps universel coordonné (UTC).
Pour obtenir la liste des tâches d’E/S courantes, consultez Tâches d’E/S courantes.