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NotifyFilters Enumeration

Specifies changes to watch for in a file or folder.

This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.

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

'Declaration
<FlagsAttribute> _
Public Enumeration NotifyFilters

Member nameDescription
AttributesThe attributes of the file or folder.
CreationTimeThe time the file or folder was created.
DirectoryNameThe name of the directory.
FileNameThe name of the file.
LastAccessThe date the file or folder was last opened.
LastWriteThe date the file or folder last had anything written to it.
SecurityThe security settings of the file or folder.
SizeThe size of the file or folder.

You can combine the members of this enumeration to watch for more than one kind of change. For example, you can watch for changes in the size of a file or folder, and for changes in security settings. This raises an event anytime there is a change in size or security settings of a file or folder.

The following example creates a FileSystemWatcher to watch the directory that is specified at runtime. The component is set to watch for any changes in LastWrite and LastAccess time, the creation, deletion, or renaming of text files in the directory. If a file is changed, created, or deleted, the path to the file prints to the console. When a file is renamed, the old and new paths print to the console.

Use the System.Diagnostics and System.IO namespaces for this example.

Imports System
Imports System.IO
Imports Microsoft.VisualBasic
Imports System.Security.Permissions

Public Class Watcher

    Public Shared Sub Main()
	
         Run()

    End Sub

    <PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
    Private Shared Sub Run

      Dim args() As String = System.Environment.GetCommandLineArgs()
        ' If a directory is not specified, exit the program. 
        If args.Length <> 2 Then 
            ' Display the proper way to call the program.
            Console.WriteLine("Usage: Watcher.exe (directory)")
            Return 
        End If 

        ' Create a new FileSystemWatcher and set its properties. 
        Dim watcher As New FileSystemWatcher()
        watcher.Path = args(1)
        ' Watch for changes in LastAccess and LastWrite times, and 
        ' the renaming of files or directories. 
        watcher.NotifyFilter = (NotifyFilters.LastAccess Or NotifyFilters.LastWrite Or NotifyFilters.FileName Or NotifyFilters.DirectoryName)
        ' Only watch text files.
        watcher.Filter = "*.txt" 

        ' Add event handlers. 
        AddHandler watcher.Changed, AddressOf OnChanged
        AddHandler watcher.Created, AddressOf OnChanged
        AddHandler watcher.Deleted, AddressOf OnChanged
        AddHandler watcher.Renamed, AddressOf OnRenamed

        ' Begin watching.
        watcher.EnableRaisingEvents = True 

        ' Wait for the user to quit the program.
        Console.WriteLine("Press 'q' to quit the sample.")
        While Chr(Console.Read()) <> "q"c
        End While 
    End Sub 

    ' Define the event handlers. 
    Private Shared Sub OnChanged(source As Object, e As FileSystemEventArgs)
        ' Specify what is done when a file is changed, created, or deleted.
        Console.WriteLine("File: " & e.FullPath & " " & e.ChangeType)
    End Sub     

    Private Shared Sub OnRenamed(source As Object, e As RenamedEventArgs)
        ' Specify what is done when a file is renamed.
        Console.WriteLine("File: {0} renamed to {1}", e.OldFullPath, e.FullPath)
    End Sub 

End Class

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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