WatcherChangeTypes 枚举

可能会发生的文件或目录更改。

此枚举有一个 FlagsAttribute 属性，允许其成员值按位组合。

**命名空间:**System.IO
**程序集:**System（在 system.dll 中）

语法

声明
<FlagsAttribute> _
Public Enumeration WatcherChangeTypes
用法
Dim instance As WatcherChangeTypes

[FlagsAttribute] 
public enum WatcherChangeTypes

[FlagsAttribute] 
public enum class WatcherChangeTypes

/** @attribute FlagsAttribute() */ 
public enum WatcherChangeTypes

FlagsAttribute 
public enum WatcherChangeTypes

成员

	成员名称	说明
	All	文件或文件夹的创建、删除、更改或重命名。
	Changed	文件或文件夹的更改。更改的类型包括大小、属性、安全设置、最近写入时间和最近访问时间方面的更改。
	Created	文件或文件夹的创建。
	Deleted	文件或文件夹的删除。
	Renamed	文件或文件夹的重命名。

备注

每个 WatcherChangeTypes 成员与 FileSystemWatcher 中的事件关联。有关事件的更多信息，请参见 Created、Deleted、Changed 和 Renamed。

示例

下面的示例演示如何创建 FileSystemWatcher，以监视磁盘驱动器上文件的改动（创建、删除、重命名和更改）。此示例还演示如何正确接收错误通知。

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

平台

Windows 98、Windows 2000 SP4、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

请参见

参考

System.IO 命名空间
FileSystemWatcher.Changed 事件
FileSystemWatcher.Created 事件
FileSystemWatcher.Deleted 事件
FileSystemEventArgs 类
FileSystemEventHandler 委托
FileSystemWatcher 类
InternalBufferOverflowException 类
NotifyFilters 枚举
FileSystemWatcher.Renamed 事件
RenamedEventArgs 类
RenamedEventHandler 委托
WaitForChangedResult 结构