IsolatedStorageFileStream.Handle-Eigenschaft

HINWEIS: Diese Eigenschaft ist mittlerweile veraltet.

Ruft das Dateihandle für die Datei ab, die vom aktuellen IsolatedStorageFileStream-Objekt gekapselt wird. Der Zugriff auf diese Eigenschaft ist für ein IsolatedStorageFileStream-Objekt nicht zulässig und löst eine IsolatedStorageException-Ausnahme aus.

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

Syntax

'Declaration
<ObsoleteAttribute("This property has been deprecated.  Please use IsolatedStorageFileStream's SafeFileHandle property instead.  https://go.microsoft.com/fwlink/?linkid=14202")> _
Public Overrides ReadOnly Property Handle As IntPtr
'Usage
Dim instance As IsolatedStorageFileStream
Dim value As IntPtr

value = instance.Handle

[ObsoleteAttribute("This property has been deprecated.  Please use IsolatedStorageFileStream\'s SafeFileHandle property instead.  https://go.microsoft.com/fwlink/?linkid=14202")] 
public override IntPtr Handle { get; }

[ObsoleteAttribute(L"This property has been deprecated.  Please use IsolatedStorageFileStream\'s SafeFileHandle property instead.  https://go.microsoft.com/fwlink/?linkid=14202")] 
public:
virtual property IntPtr Handle {
    IntPtr get () override;
}

/** @property */
public IntPtr get_Handle ()

public override function get Handle () : IntPtr

Eigenschaftenwert

Das Dateihandle für die Datei, die vom aktuellen IsolatedStorageFileStream-Objekt gekapselt wird.

Ausnahmen

Hinweise

Weitere Informationen finden Sie unter Handle.

Beispiel

Das folgende Codebeispiel veranschaulicht die Handle-Eigenschaft.

Private Function GetPrefsForUser() As Boolean
    Try
        ' Retrieve an IsolatedStorageFile for the current Domain and Assembly.
        Dim isoFile As IsolatedStorageFile = _
            IsolatedStorageFile.GetStore(IsolatedStorageScope.User _
            Or IsolatedStorageScope.Assembly _
            Or IsolatedStorageScope.Domain, Nothing, Nothing)

        Dim isoStream As New IsolatedStorageFileStream(Me.userName, FileMode.Open, _
            FileAccess.Read, FileShare.Read)
        ' farThe code executes to this point only if a file corresponding to the username exists.
        ' Though you can perform operations on the stream, you cannot get a handle to the file.
        Try

            Dim aFileHandle As SafeFileHandle = isoStream.SafeFileHandle
            Console.WriteLine(("A pointer to a file handle has been obtained. " & aFileHandle.ToString() & " " & aFileHandle.GetHashCode()))

        Catch ex As Exception
            ' Handle the exception.
            Console.WriteLine("Expected exception")
            Console.WriteLine(ex.ToString())
        End Try

        Dim reader As New StreamReader(isoStream)
        ' Read the data.
        Me.NewsUrl = reader.ReadLine()
        Me.SportsUrl = reader.ReadLine()
        reader.Close()
        isoFile.Close()
        Return False
    Catch ex As System.IO.FileNotFoundException
        ' Expected exception if a file cannot be found. This indicates that we have a new user.
        Return True
    End Try
End Function 'GetPrefsForUser

private bool GetPrefsForUser()
{
    try
    {

        // Retrieve an IsolatedStorageFile for the current Domain and Assembly.
        IsolatedStorageFile isoFile =
            IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
            IsolatedStorageScope.Assembly |
            IsolatedStorageScope.Domain,
            null,
            null);

        IsolatedStorageFileStream isoStream =
            new IsolatedStorageFileStream(this.userName,
            FileMode.Open,
            FileAccess.Read,
            FileShare.Read);

        // The code executes to this point only if a file corresponding to the username exists.
        // Though you can perform operations on the stream, you cannot get a handle to the file.

        try
        {

            SafeFileHandle aFileHandle = isoStream.SafeFileHandle;
            Console.WriteLine("A pointer to a file handle has been obtained. "
                + aFileHandle.ToString() + " "
                + aFileHandle.GetHashCode());
        }

        catch (Exception e)
        {
            // Handle the exception.
            Console.WriteLine("Expected exception");
            Console.WriteLine(e);
        }

        StreamReader reader = new StreamReader(isoStream);
        // Read the data.
        this.NewsUrl = reader.ReadLine();
        this.SportsUrl = reader.ReadLine();
        reader.Close();
        isoFile.Close();
        return false;
    }
    catch (System.IO.FileNotFoundException)
    {
        // Expected exception if a file cannot be found. This indicates that we have a new user.
        return true;
    }
}

[SecurityPermissionAttribute(SecurityAction::Demand, Flags=SecurityPermissionFlag::UnmanagedCode)]
bool GetPrefsForUser()
{
   try
   {
      
      // Retrieve an IsolatedStorageFile for the current Domain and Assembly.
      IsolatedStorageFile^ isoFile = IsolatedStorageFile::GetStore( static_cast<IsolatedStorageScope>(IsolatedStorageScope::User | IsolatedStorageScope::Assembly | IsolatedStorageScope::Domain), (Type^)nullptr, nullptr );
      IsolatedStorageFileStream^ isoStream = gcnew IsolatedStorageFileStream( this->userName,FileMode::Open,FileAccess::ReadWrite,isoFile );
      
      // farThe code executes to this point only if a file corresponding to the username exists.
      // Though you can perform operations on the stream, you cannot get a handle to the file.
      try
      {
         IntPtr aFileHandle = isoStream->Handle;
         Console::WriteLine( "A pointer to a file handle has been obtained. {0} {1}", aFileHandle, aFileHandle.GetHashCode() );
      }
      catch ( Exception^ e ) 
      {
         
         // Handle the exception.
         Console::WriteLine( "Expected exception" );
         Console::WriteLine( e->ToString() );
      }

      StreamReader^ reader = gcnew StreamReader( isoStream );
      
      // Read the data.
      this->NewsUrl = reader->ReadLine();
      this->SportsUrl = reader->ReadLine();
      reader->Close();
      isoFile->Close();
      isoStream->Close();
      return false;
   }
   catch ( Exception^ e ) 
   {
      
      // Expected exception if a file cannot be found. This indicates that we have a new user.
      String^ errorMessage = e->ToString();
      return true;
   }

}

.NET Framework-Sicherheit

• SecurityPermission  für den Zugriff auf nicht verwalteten Code. Zugeordnete Enumeration: SecurityPermissionFlag.UnmanagedCode

Plattformen

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

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 1.0, 1.1
Veraltet (Compilerwarnung) in 2.0

Siehe auch

Referenz

IsolatedStorageFileStream-Klasse
IsolatedStorageFileStream-Member
System.IO.IsolatedStorage-Namespace