Επεξεργασία

Κοινή χρήση μέσω


File.GetLastAccessTime Method

Definition

Overloads

GetLastAccessTime(SafeFileHandle)

Returns the last access date and time of the specified file or directory.

GetLastAccessTime(String)

Returns the date and time the specified file or directory was last accessed.

GetLastAccessTime(SafeFileHandle)

Source:
File.cs
Source:
File.cs
Source:
File.cs

Returns the last access date and time of the specified file or directory.

public:
 static DateTime GetLastAccessTime(Microsoft::Win32::SafeHandles::SafeFileHandle ^ fileHandle);
public static DateTime GetLastAccessTime (Microsoft.Win32.SafeHandles.SafeFileHandle fileHandle);
static member GetLastAccessTime : Microsoft.Win32.SafeHandles.SafeFileHandle -> DateTime
Public Shared Function GetLastAccessTime (fileHandle As SafeFileHandle) As DateTime

Parameters

fileHandle
SafeFileHandle

A SafeFileHandle to the file or directory for which to obtain last access date and time information.

Returns

A DateTime structure set to the last access date and time for the specified file or directory. This value is expressed in local time.

Exceptions

fileHandle is null.

The caller does not have the required permission.

Applies to

GetLastAccessTime(String)

Source:
File.cs
Source:
File.cs
Source:
File.cs

Returns the date and time the specified file or directory was last accessed.

public:
 static DateTime GetLastAccessTime(System::String ^ path);
public static DateTime GetLastAccessTime (string path);
static member GetLastAccessTime : string -> DateTime
Public Shared Function GetLastAccessTime (path As String) As DateTime

Parameters

path
String

The file or directory for which to obtain access date and time information.

Returns

A DateTime structure set to the date and time that the specified file or directory was last accessed. This value is expressed in local time.

Exceptions

The caller does not have the required permission.

.NET Framework and .NET Core versions older than 2.1: path is a zero-length string, contains only white space, or contains one or more invalid characters. You can query for invalid characters by using the GetInvalidPathChars() method.

path is null.

The specified path, file name, or both exceed the system-defined maximum length.

path is in an invalid format.

Examples

The following example demonstrates GetLastAccessTime.

using namespace System;
using namespace System::IO;
int main()
{
   try
   {
      String^ path = "c:\\Temp\\MyTest.txt";
      if (  !File::Exists( path ) )
      {
         File::Create( path );
      }
      File::SetLastAccessTime( path, DateTime(1985,5,4) );
      
      // Get the creation time of a well-known directory.
      DateTime dt = File::GetLastAccessTime( path );
      Console::WriteLine( "The last access time for this file was {0}.", dt );
      
      // Update the last access time.
      File::SetLastAccessTime( path, DateTime::Now );
      dt = File::GetLastAccessTime( path );
      Console::WriteLine( "The last access time for this file was {0}.", dt );
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "The process failed: {0}", e );
   }

}
using System;
using System.IO;

class Test
{
    public static void Main()
    {
        try
        {
            string path = @"c:\Temp\MyTest.txt";

            if (!File.Exists(path))
            {
                File.Create(path);
            }
            File.SetLastAccessTime(path, new DateTime(1985,5,4));

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

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

let path = @"c:\Temp\MyTest.txt"

if File.Exists path |> not then
    File.Create path |> ignore

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

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

// Update the last access time.
File.SetLastAccessTime(path, DateTime.Now)
let dt2 = File.GetLastAccessTime path
printfn $"The last access time for this file was {dt2}."
Imports System.IO
Imports System.Text

Public Class Test
    Public Shared Sub Main()
        Try
            Dim path As String = "c:\Temp\MyTest.txt"
            If File.Exists(path) = False Then
                File.Create(path)
            End If
            File.SetLastAccessTime(path, New DateTime(1985, 5, 4))

            ' Get the creation time of a well-known directory.
            Dim dt As DateTime = File.GetLastAccessTime(path)

            Console.WriteLine("The last access time for this file was {0}.", dt)

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

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

Remarks

Note

This method may return an inaccurate value, because it uses native functions whose values may not be continuously updated by the operating system.

If the file described in the path parameter does not exist, this method returns 12:00 midnight, January 1, 1601 A.D. (C.E.) Coordinated Universal Time (UTC), adjusted to local time.

The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.

For a list of common I/O tasks, see Common I/O Tasks.

See also

Applies to