FileSystemWatcher.Path Proprietà

Definizione

Ottiene o imposta il percorso della directory da controllare.Gets or sets the path of the directory to watch.

public:
 property System::String ^ Path { System::String ^ get(); void set(System::String ^ value); };
public string Path { get; set; }
[System.ComponentModel.TypeConverter("System.Diagnostics.Design.StringValueConverter, System.Design, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
[System.IO.IODescription("FSW_Path")]
public string Path { get; set; }
[System.IO.IODescription("FSW_Path")]
[System.ComponentModel.TypeConverter("System.Diagnostics.Design.StringValueConverter, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
public string Path { get; set; }
[System.ComponentModel.TypeConverter("System.Diagnostics.Design.StringValueConverter, System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
[System.IO.IODescription("FSW_Path")]
[System.ComponentModel.SettingsBindable(true)]
public string Path { get; set; }
[System.ComponentModel.SettingsBindable(true)]
public string Path { get; set; }
[System.ComponentModel.TypeConverter("System.Diagnostics.Design.StringValueConverter, System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")]
[System.IO.IODescription("The directory to monitor")]
public string Path { get; set; }
member this.Path : string with get, set
Public Property Path As String

Valore della proprietà

Percorso da monitorare.The path to monitor. Il valore predefinito è una stringa vuota ("").The default is an empty string ("").

Attributi

Eccezioni

Il percorso specificato non esiste o non è stata trovato.The specified path does not exist or could not be found.

-oppure--or-

Il percorso specificato contiene caratteri jolly.The specified path contains wildcard characters.

-oppure--or-

Il percorso specificato contiene caratteri di percorso non validi.The specified path contains invalid path characters.

Esempio

Nell'esempio seguente viene creato un FileSystemWatcher per controllare la directory specificata in fase di esecuzione.The following example creates a FileSystemWatcher to watch the directory specified at run time. Il componente è impostato in modo da controllare le modifiche in LastWrite e LastAccess tempo, la creazione, l'eliminazione o la ridenominazione dei file di testo nella directory.The component is set to watch for changes in LastWrite and LastAccess time, the creation, deletion, or renaming of text files in the directory. Se un file viene modificato, creato o eliminato, il percorso del file viene stampato nella console.If a file is changed, created, or deleted, the path to the file prints to the console. Quando un file viene rinominato, i percorsi vecchi e nuovi vengono stampati nella console.When a file is renamed, the old and new paths print to the console.

#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Security::Permissions;

public ref class Watcher
{
private:
   // Define the event handlers.
   static void OnChanged( Object^ /*source*/, FileSystemEventArgs^ e )
   {
      // Specify what is done when a file is changed, created, or deleted.
      Console::WriteLine( "File: {0} {1}", e->FullPath, e->ChangeType );
   }

   static void OnRenamed( Object^ /*source*/, RenamedEventArgs^ e )
   {
      // Specify what is done when a file is renamed.
      Console::WriteLine( "File: {0} renamed to {1}", e->OldFullPath, e->FullPath );
   }

public:
   [PermissionSet(SecurityAction::Demand, Name="FullTrust")]
   int static run()
   {
      array<String^>^args = System::Environment::GetCommandLineArgs();

      // If a directory is not specified, exit program.
      if ( args->Length != 2 )
      {
         // Display the proper way to call the program.
         Console::WriteLine( "Usage: Watcher.exe (directory)" );
         return 0;
      }

      // Create a new FileSystemWatcher and set its properties.
      FileSystemWatcher^ watcher = gcnew FileSystemWatcher;
      watcher->Path = args[ 1 ];

      /* Watch for changes in LastAccess and LastWrite times, and 
          the renaming of files or directories. */
      watcher->NotifyFilter = static_cast<NotifyFilters>(NotifyFilters::LastAccess |
            NotifyFilters::LastWrite | NotifyFilters::FileName | NotifyFilters::DirectoryName);

      // Only watch text files.
      watcher->Filter = "*.txt";

      // Add event handlers.
      watcher->Changed += gcnew FileSystemEventHandler( Watcher::OnChanged );
      watcher->Created += gcnew FileSystemEventHandler( Watcher::OnChanged );
      watcher->Deleted += gcnew FileSystemEventHandler( Watcher::OnChanged );
      watcher->Renamed += gcnew RenamedEventHandler( Watcher::OnRenamed );

      // Begin watching.
      watcher->EnableRaisingEvents = true;

      // Wait for the user to quit the program.
      Console::WriteLine( "Press \'q\' to quit the sample." );
      while ( Console::Read() != 'q' );

      return 0;
   }
};

int main() {
   Watcher::run();
}
using System;
using System.IO;
using System.Security.Permissions;

public class Watcher
{
    public static void Main()
    {
        Run();
    }

    [PermissionSet(SecurityAction.Demand, Name = "FullTrust")]
    private static void Run()
    {
        string[] args = Environment.GetCommandLineArgs();

        // If a directory is not specified, exit program.
        if (args.Length != 2)
        {
            // Display the proper way to call the program.
            Console.WriteLine("Usage: Watcher.exe (directory)");
            return;
        }

        // Create a new FileSystemWatcher and set its properties.
        using (FileSystemWatcher watcher = 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
                                 | NotifyFilters.LastWrite
                                 | NotifyFilters.FileName
                                 | NotifyFilters.DirectoryName;

            // Only watch text files.
            watcher.Filter = "*.txt";

            // Add event handlers.
            watcher.Changed += OnChanged;
            watcher.Created += OnChanged;
            watcher.Deleted += OnChanged;
            watcher.Renamed += OnRenamed;

            // Begin watching.
            watcher.EnableRaisingEvents = true;

            // Wait for the user to quit the program.
            Console.WriteLine("Press 'q' to quit the sample.");
            while (Console.Read() != 'q') ;
        }
    }

    // Define the event handlers.
    private static void OnChanged(object source, FileSystemEventArgs e) =>
        // Specify what is done when a file is changed, created, or deleted.
        Console.WriteLine($"File: {e.FullPath} {e.ChangeType}");

    private static void OnRenamed(object source, RenamedEventArgs e) =>
        // Specify what is done when a file is renamed.
        Console.WriteLine($"File: {e.OldFullPath} renamed to {e.FullPath}");
}
Imports System.IO
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 = 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.
        Using 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 Using
    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: {e.OldFullPath} renamed to {e.FullPath}")
    End Sub

End Class

Commenti

Si tratta di un percorso completo di una directory.This is a fully qualified path to a directory. Se la proprietà IncludeSubdirectories è true, questa directory è la radice in cui il sistema controlla le modifiche. in caso contrario, si tratta dell'unica directory controllata.If the IncludeSubdirectories property is true, this directory is the root at which the system watches for changes; otherwise it is the only directory watched. Per controllare un file specifico, impostare la proprietà Path sulla directory completa, corretta e la proprietà Filter sul nome del file.To watch a specific file, set the Path property to the fully qualified, correct directory, and the Filter property to the file name.

La proprietà Path supporta i percorsi di Universal Naming Convention (UNC).The Path property supports Universal Naming Convention (UNC) paths.

Nota

Questa proprietà deve essere impostata prima che il componente possa controllare le modifiche.This property must be set before the component can watch for changes.

Quando una directory viene rinominata, il FileSystemWatcher si riconnette automaticamente all'elemento appena rinominato.When a directory is renamed, the FileSystemWatcher automatically reattaches itself to the newly renamed item. Se, ad esempio, si imposta la proprietà Path su "C:\My Documents" e quindi si rinomina manualmente la directory in "C:\Your Documents", il componente continua ad ascoltare le notifiche di modifica sulla nuova directory rinominata.For example, if you set the Path property to "C:\My Documents" and then manually rename the directory to "C:\Your Documents", the component continues listening for change notifications on the newly renamed directory. Tuttavia, quando si richiede la proprietà Path, contiene il percorso precedente.However, when you ask for the Path property, it contains the old path. Questo problema si verifica perché il componente determina la directory che controlla in base all'handle, anziché il nome della directory.This happens because the component determines what directory watches based on the handle, rather than the name of the directory. La ridenominazione non influisce sull'handle.Renaming does not affect the handle. Se quindi si elimina il componente e quindi lo si ricrea senza aggiornare la proprietà Path, l'applicazione avrà esito negativo perché la directory non esiste più.So, if you destroy the component, and then recreate it without updating the Path property, your application will fail because the directory no longer exists.

Si applica a

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