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File.SetLastAccessTime Method

Definition

Overloads

SetLastAccessTime(String, DateTime)

Sets the date and time the specified file was last accessed.

SetLastAccessTime(SafeFileHandle, DateTime)

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

SetLastAccessTime(String, DateTime)

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

Sets the date and time the specified file was last accessed.

public static void SetLastAccessTime (string path, DateTime lastAccessTime);

Parameters

path
String

The file for which to set the access date and time information.

lastAccessTime
DateTime

A DateTime containing the value to set for the last access date and time of path. This value is expressed in local time.

Exceptions

.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.

The specified path was not found.

The caller does not have the required permission.

path is in an invalid format.

lastAccessTime specifies a value outside the range of dates or times permitted for this operation.

Examples

The following example checks the file system for the specified file, creating it if necessary, and then sets and gets the last access time.

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);
                // Update the last access time.	
            }
            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());
        }
    }
}

Remarks

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

.NET 9 en andere versies
Product Versies
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0

SetLastAccessTime(SafeFileHandle, DateTime)

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

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

public static void SetLastAccessTime (Microsoft.Win32.SafeHandles.SafeFileHandle fileHandle, DateTime lastAccessTime);

Parameters

fileHandle
SafeFileHandle

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

lastAccessTime
DateTime

A DateTime containing the value to set for the last access date and time of fileHandle. This value is expressed in local time.

Exceptions

fileHandle is null.

lastAccessTime specifies a value outside the range of dates, times, or both permitted for this operation.

The caller does not have the required permission.

An I/O error occurred while performing the operation.

Applies to

.NET 9 en andere versies
Product Versies
.NET 7, 8, 9