WatcherChangeTypes Enumeração
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Alterações que podem ocorrer em um arquivo ou diretório.
Essa enumeração dá suporte a uma combinação bit a bit dos valores de membro.
public enum class WatcherChangeTypes
[System.Flags]
public enum WatcherChangeTypes
[<System.Flags>]
type WatcherChangeTypes =
Public Enum WatcherChangeTypes
- Herança
- Atributos
Campos
All | 15 | A criação, exclusão, alteração ou a renomeação de um arquivo ou uma pasta. |
Changed | 4 | A alteração de um arquivo ou uma pasta. Os tipos de alterações incluem: alterações de tamanho, atributos, configurações de segurança, última gravação e hora do último acesso. |
Created | 1 | A criação de um arquivo ou uma pasta. |
Deleted | 2 | A exclusão de um arquivo ou uma pasta. |
Renamed | 8 | A renomeação de um arquivo ou uma pasta. |
Exemplos
O exemplo a seguir mostra como criar um FileSystemWatcher para monitorar alterações de arquivo (cria, exclui, renomeia, alterações) que ocorrem em uma unidade de disco. O exemplo também mostra como receber corretamente notificações de erro.
using System;
using System.IO;
class Program
{
static void Main(string[] args)
{
// Create a FileSystemWatcher to monitor all files on drive C.
FileSystemWatcher fsw = new FileSystemWatcher("C:\\");
// Watch for changes in LastAccess and LastWrite times, and
// the renaming of files or directories.
fsw.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite
| NotifyFilters.FileName |NotifyFilters.DirectoryName;
// Register a handler that gets called when a
// file is created, changed, or deleted.
fsw.Changed += new FileSystemEventHandler(OnChanged);
fsw.Created += new FileSystemEventHandler(OnChanged);
fsw.Deleted += new FileSystemEventHandler(OnChanged);
// Register a handler that gets called when a file is renamed.
fsw.Renamed += new RenamedEventHandler(OnRenamed);
// Register a handler that gets called if the
// FileSystemWatcher needs to report an error.
fsw.Error += new ErrorEventHandler(OnError);
// Begin watching.
fsw.EnableRaisingEvents = true;
Console.WriteLine("Press \'Enter\' to quit the sample.");
Console.ReadLine();
}
// This method is called when a file is created, changed, or deleted.
private static void OnChanged(object source, FileSystemEventArgs e)
{
// Show that a file has been created, changed, or deleted.
WatcherChangeTypes wct = e.ChangeType;
Console.WriteLine("File {0} {1}", e.FullPath, wct.ToString());
}
// This method is called when a file is renamed.
private static void OnRenamed(object source, RenamedEventArgs e)
{
// Show that a file has been renamed.
WatcherChangeTypes wct = e.ChangeType;
Console.WriteLine("File {0} {2} to {1}", e.OldFullPath, e.FullPath, wct.ToString());
}
// This method is called when the FileSystemWatcher detects an error.
private static void OnError(object source, ErrorEventArgs e)
{
// Show that an error has been detected.
Console.WriteLine("The FileSystemWatcher has detected an error");
// Give more information if the error is due to an internal buffer overflow.
if (e.GetException().GetType() == typeof(InternalBufferOverflowException))
{
// This can happen if Windows is reporting many file system events quickly
// and internal buffer of the FileSystemWatcher is not large enough to handle this
// rate of events. The InternalBufferOverflowException error informs the application
// that some of the file system events are being lost.
Console.WriteLine(("The file system watcher experienced an internal buffer overflow: " + e.GetException().Message));
}
}
}
Imports System.IO
Module Module1
Sub Main()
' Create a FileSystemWatcher to monitor all files on drive C.
Dim fsw As New FileSystemWatcher("C:\")
' Watch for changes in LastAccess and LastWrite times, and
' the renaming of files or directories.
fsw.NotifyFilter = (NotifyFilters.LastAccess Or NotifyFilters.LastWrite _
Or NotifyFilters.FileName Or NotifyFilters.DirectoryName)
' Register a handler that gets called when a
' file is created, changed, or deleted.
AddHandler fsw.Changed, New FileSystemEventHandler(AddressOf OnChanged)
' The commented line of code below is a shorthand of the above line.
' AddHandler fsw.Changed, AddressOf OnChanged
' NOTE: The shorthand version is used in the remainder of this code.
' FileSystemEventHandler
AddHandler fsw.Created, AddressOf OnChanged
' FileSystemEventHandler
AddHandler fsw.Deleted, AddressOf OnChanged
' Register a handler that gets called when a file is renamed.
' RenamedEventHandler
AddHandler fsw.Renamed, AddressOf OnRenamed
' Register a handler that gets called if the
' FileSystemWatcher needs to report an error.
' ErrorEventHandler
AddHandler fsw.Error, AddressOf OnError
' Begin watching.
fsw.EnableRaisingEvents = True
' Wait for the user to quit the program.
Console.WriteLine("Press 'Enter' to quit the sample.")
Console.ReadLine()
End Sub
' This method is called when a file is created, changed, or deleted.
Private Sub OnChanged(ByVal source As Object, ByVal e As FileSystemEventArgs)
' Show that a file has been created, changed, or deleted.
Dim wct As WatcherChangeTypes = e.ChangeType
Console.WriteLine("File {0} {1}", e.FullPath, wct.ToString())
End Sub
' This method is called when a file is renamed.
Private Sub OnRenamed(ByVal source As Object, ByVal e As RenamedEventArgs)
' Show that a file has been renamed.
Dim wct As WatcherChangeTypes = e.ChangeType
Console.WriteLine("File {0} {2} to {1}", e.OldFullPath, e.FullPath, wct.ToString())
End Sub
' This method is called when the FileSystemWatcher detects an error.
Private Sub OnError(ByVal source As Object, ByVal e As ErrorEventArgs)
' Show that an error has been detected.
Console.WriteLine("The FileSystemWatcher has detected an error")
' Give more information if the error is due to an internal buffer overflow.
If TypeOf e.GetException Is InternalBufferOverflowException Then
' This can happen if Windows is reporting many file system events quickly
' and internal buffer of the FileSystemWatcher is not large enough to handle this
' rate of events. The InternalBufferOverflowException error informs the application
' that some of the file system events are being lost.
Console.WriteLine( _
"The file system watcher experienced an internal buffer overflow: " _
+ e.GetException.Message)
End If
End Sub
End Module
Comentários
Cada WatcherChangeTypes membro é associado a um evento no FileSystemWatcher. Para obter mais informações sobre os eventos, consulte Created, Deleted, Changede Renamed.