SetLastAccessTime Method

Directory.SetLastAccessTime Method (String, DateTime)


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

Namespace:   System.IO
Assembly:  mscorlib (in mscorlib.dll)

public static void SetLastAccessTime(
	string path,
	DateTime lastAccessTime


Type: System.String

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

Type: System.DateTime

An object that contains the value to set for the access date and time of path. This value is expressed in local time.

Exception Condition

The specified path was not found.


path is a zero-length string, contains only white space, or contains one or more invalid characters. You can query for invalid characters with the GetInvalidPathChars method.


path is null.


The specified path, file name, or both exceed the system-defined maximum length. For example, on Windows-based platforms, paths must be less than 248 characters and file names must be less than 260 characters.


The caller does not have the required permission.


The current operating system is not Windows NT or later.


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

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.

The path parameter is not case-sensitive.

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


These operating systems do not support this method.

The following example demonstrates how to use SetLastAccessTime.

using System;
using System.IO;

class Test 
    public static void Main() 
            string path = @"c:\MyDir";
            if (!Directory.Exists(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());

for writing to the specified file or directory. Associated enumeration: FileIOPermissionAccess.Write

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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