OpenFileDialog.ShowReadOnly Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene o imposta un valore che indica se la finestra di dialogo contiene una casella di controllo di sola lettura.
public:
property bool ShowReadOnly { bool get(); void set(bool value); };
public bool ShowReadOnly { get; set; }
member this.ShowReadOnly : bool with get, set
Public Property ShowReadOnly As Boolean
Valore della proprietà
true
se la finestra di dialogo contiene una casella di controllo di sola lettura; in caso contrario, false
. Il valore predefinito è false
.
Esempio
Nell'esempio di codice seguente viene illustrato l'uso ShowReadOnly della proprietà. In questo esempio viene visualizzata la OpenFileDialog casella con la ShowReadOnly proprietà impostata su true
. Se l'utente fa clic sull'opzione per aprire il file in modalità di sola lettura, il OpenFile metodo viene usato per aprire il file. In caso contrario, la FileStream classe viene usata per aprire il file in modalità di lettura/scrittura.
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 == true )
{
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 == true)
{
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