OpenFileDialog.ReadOnlyChecked Eigenschap

Definitie

Hiermee wordt een waarde opgehaald of ingesteld die aangeeft of het selectievakje Alleen-lezen is ingeschakeld.

public:
 property bool ReadOnlyChecked { bool get(); void set(bool value); };
public bool ReadOnlyChecked { get; set; }
member this.ReadOnlyChecked : bool with get, set
Public Property ReadOnlyChecked As Boolean

Waarde van eigenschap

true als het selectievakje Alleen-lezen is ingeschakeld; anders, false. De standaardwaarde is false.

Voorbeelden

In het volgende codevoorbeeld ziet u hoe de ReadOnlyChecked eigenschap wordt gebruikt. In dit voorbeeld wordt het OpenFileDialog vak weergegeven waarop de ShowReadOnly eigenschap is ingesteld op true. Als de gebruiker op de optie klikt om het bestand te openen in de modus Alleen-lezen, wordt de ReadOnlyChecked eigenschap geƫvalueerd trueen wordt de OpenFile methode gebruikt om het bestand te openen. Anders wordt de FileStream klasse gebruikt om het bestand te openen in de lees-/schrijfmodus.

private:
   FileStream^ OpenFile()
   {
      // Displays an OpenFileDialog and shows the read/only files.
      OpenFileDialog^ dlgOpenFile = gcnew OpenFileDialog;
      dlgOpenFile->ShowReadOnly = true;
      if ( dlgOpenFile->ShowDialog() == ::DialogResult::OK )
      {
         // If ReadOnlyChecked is true, uses the OpenFile method to
         // open the file with read/only access.
         if ( dlgOpenFile->ReadOnlyChecked )
         {
            return dynamic_cast<FileStream^>(dlgOpenFile->OpenFile());
         }
         // Otherwise, opens the file with read/write access.
         else
         {
            String^ path = dlgOpenFile->FileName;
            return gcnew FileStream( path,System::IO::FileMode::Open,System::IO::FileAccess::ReadWrite );
         }
      }

      return nullptr;
   }
private FileStream OpenFile()
{
    // Displays an OpenFileDialog and shows the read/only files.

    OpenFileDialog dlgOpenFile = new OpenFileDialog();
    dlgOpenFile.ShowReadOnly = true;

    if(dlgOpenFile.ShowDialog() == DialogResult.OK)
    {

        // If ReadOnlyChecked is true, uses the OpenFile method to
        // open the file with read/only access.
        string path = null;

        try {
            if (dlgOpenFile.ReadOnlyChecked)
            {
                return (FileStream)dlgOpenFile.OpenFile();
            }

            // Otherwise, opens the file with read/write access.
            else
            {
                path = dlgOpenFile.FileName;
                return new FileStream(path, System.IO.FileMode.Open,
                            System.IO.FileAccess.ReadWrite);
            }
        } catch (SecurityException ex)
            {
                // The user lacks appropriate permissions to read files, discover paths, etc.
                MessageBox.Show("Security error. Please contact your administrator for details.\n\n" +
                    "Error message: " + ex.Message + "\n\n" +
                    "Details (send to Support):\n\n" + ex.StackTrace
                );
            }
            catch (Exception ex)
            {
                // Could not load the image - probably related to Windows file system permissions.
                MessageBox.Show("Cannot display the image: " + path.Substring(path.LastIndexOf('\\'))
                    + ". You may not have permission to read the file, or " +
                    "it may be corrupt.\n\nReported error: " + ex.Message);
            }
    }

    return null;
}

Private Function OpenFile() As FileStream

    ' Displays an OpenFileDialog and shows the read/only files.

    Dim DlgOpenFile As New OpenFileDialog()
    DlgOpenFile.ShowReadOnly = True

    If DlgOpenFile.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
        Dim path As New String("")

        ' If ReadOnlyChecked is true, uses the OpenFile method to
        ' open the file with read/only access.
        Try
            If (DlgOpenFile.ReadOnlyChecked = True) Then
                Return DlgOpenFile.OpenFile()
            Else
                ' Otherwise, opens the file with read/write access.
                Path = DlgOpenFile.FileName
                Return New FileStream(Path, System.IO.FileMode.Open, _
                        System.IO.FileAccess.ReadWrite)
            End If
        Catch SecEx As SecurityException
            ' The user lacks appropriate permissions to read files, discover paths, etc.
            MessageBox.Show("Security error. Please contact your administrator for details.\n\n" & _
                "Error message: " & SecEx.Message * "\n\n" & _
                "Details (send to Support):\n\n" & SecEx.StackTrace)
        Catch Ex As Exception
            ' Could not load the image - probably related to Windows file system permissions.
            MessageBox.Show("Cannot display the image: " & path.Substring(path.LastIndexOf("\\")) & _
                     ". You may not have permission to read the file, or " & _
                    "it may be corrupt.\n\nReported error: " + ex.Message)
        End Try
    End If

    Return Nothing
End Function

Opmerkingen

De ReadOnlyChecked status heeft geen invloed op de lees-/schrijfmodus die wordt gebruikt om een bestand te openen dat OpenFileDialog.OpenFile is geselecteerd in het dialoogvenster. OpenFile opent het bestand altijd in de modus Alleen-lezen.

De ShowReadOnly eigenschap moet worden ingesteld voordat het selectievakje Alleen-lezen moet worden weergegeven in het dialoogvenster.

Van toepassing op

Zie ook