Directory.SetLastAccessTime(String, DateTime) 方法

定义

设置上次访问指定文件或目录的日期和时间。

public:
 static void SetLastAccessTime(System::String ^ path, DateTime lastAccessTime);
public static void SetLastAccessTime(string path, DateTime lastAccessTime);
static member SetLastAccessTime : string * DateTime -> unit
Public Shared Sub SetLastAccessTime (path As String, lastAccessTime As DateTime)

参数

path
String

要为其设置访问日期和时间信息的文件或目录。

lastAccessTime
DateTime

一个对象,该对象包含为访问日期和时间 path设置的值。 此值以本地时间表示。

例外

找不到指定的路径。

低于 2.1 的 .NET Framework 和 .NET Core 版本: path 是长度为零的字符串,仅包含空格,或包含一个或多个无效字符。 可以使用该方法查询无效字符 GetInvalidPathChars()

pathnull

指定的路径、文件名或两者都超过了系统定义的最大长度。

调用方没有所需的权限。

当前操作系统不是 Windows NT 或更高版本。

lastAccessTime 指定超出此操作允许的日期或时间范围的值。

示例

以下示例演示如何使用 SetLastAccessTime

using System;
using System.IO;

class Test
{
    public static void Main()
    {
        try
        {
            string path = @"c:\MyDir";
            if (!Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }
            Directory.SetLastAccessTime(path, new DateTime(1985,5,4));

            // Get the last access time of a well-known directory.
            DateTime dt = Directory.GetLastAccessTime(path);
            Console.WriteLine("The last access time for this directory was {0}", dt);
            
            // Update the last access time.
            Directory.SetLastAccessTime(path, DateTime.Now);
            dt = Directory.GetLastAccessTime(path);
            Console.WriteLine("The last access time for this directory was {0}", dt);
        }

        catch (Exception e)
        {
            Console.WriteLine("The process failed: {0}", e.ToString());
        }
    }
}
open System
open System.IO

try
    let path = @"c:\MyDir"
    if not (Directory.Exists path) then
        Directory.CreateDirectory path |> ignore

    Directory.SetLastAccessTime(path, DateTime(1985,5,4))

    // Get the last access time of a well-known directory.
    let dt = Directory.GetLastAccessTime path
    printfn $"The last access time for this directory was {dt}"

    // Update the last access time.
    Directory.SetLastAccessTime(path, DateTime.Now)
    let dt = Directory.GetLastAccessTime path
    printfn $"The last access time for this directory was {dt}"

with e ->
    printfn $"The process failed: {e}"
Imports System.IO

Public Class Test
    Public Shared Sub Main()
        Try
            Dim path As String = "c:\MyDir"
            If Directory.Exists(path) = False Then
                Directory.CreateDirectory(path)
            End If
            Directory.SetLastAccessTime(path, New DateTime(1985, 5, 4))

            'Get the last access time of a well-known directory.
            Dim dt As DateTime = Directory.GetLastAccessTime(path)
            Console.WriteLine("The last access time for this directory was {0}", dt)

            'Update the last access time.
            Directory.SetLastAccessTime(path, DateTime.Now)
            dt = Directory.GetLastAccessTime(path)
            Console.WriteLine("The last access time for this directory was {0}", dt)

        Catch e As Exception
            Console.WriteLine("The process failed: {0}", e.ToString())
        End Try
    End Sub
End Class

注解

允许参数 path 指定相对路径或绝对路径信息。 相对路径信息解释为相对于当前工作目录。 若要获取当前工作目录,请参阅 GetCurrentDirectory

参数的 path 区分大小写对应于运行代码的文件系统。 例如,它在 NTFS(默认 Windows 文件系统)上不区分大小写,在 Linux 文件系统上区分大小写。

有关常见 I/O 任务的列表,请参阅 常见 I/O 任务

适用于

另请参阅