Dialogs.TOpenOptions Type

TOpenOption and TOpenOptions determine the behavior of a file selection dialog.

Pascal

TOpenOptions = set of TOpenOption;

C++

TOpenOption TOpenOptions;

File

Dialogs

Description

TOpenOption values determine the appearance and behavior of a file selection dialog. TOpenOptions is a set of TOpenOption values.

The following table lists the possible values:

Value	Meaning
ofReadOnly	Selects the Open As Read Only check box by default when the dialog opens.
ofOverwritePrompt	Generates a warning message if the user tries to select a file name that is already in use, asking whether to overwrite the existing file. (Use with save dialogs.)
ofHideReadOnly	Removes the Open As Read Only check box from the dialog.
ofNoChangeDir	After the user clicks OK, resets the current directory to whatever it was before the file-selection dialog opened.
ofShowHelp	Displays a Help button in the dialog.
ofNoValidate	Disables checking for invalid characters in file names. Allows selection of file names with invalid characters.
ofAllowMultiSelect	Allows users to select more than one file in the dialog.
ofExtensionDifferent	This flag is turned on at runtime whenever the selected filename has an extension that differs from DefaultExt. If you use this flag in an application, remember to reset it.
ofPathMustExist	Generates an error message if the user tries to select a file name with a nonexistent directory path.
ofFileMustExist	Generates an error message if the user tries to select a nonexistent file. (only applies to Open dialogs).
ofCreatePrompt	Generates a warning message if the user tries to select a nonexistent file, asking whether to create a new file with the specified name.
ofShareAware	Ignores sharing errors and allows files to be selected even when sharing violations occur.
ofNoReadOnlyReturn	Generates an error message if the user tries to select a read-only file.
ofNoTestFileCreate	Disables checking for network file protection and inaccessibility of disk drives. Applies only when the user tries to save a file in a create-no-modify shared network directory.
ofNoNetworkButton	Removes the Network button (which opens a Map Network Drive dialog) from the file-selection dialog. Applies only if the ofOldStyleDialog flag is on.
ofNoLongNames	Displays 8.3-character file names only. This option is only valid if Options also includes ofOldStyleDialog.
ofOldStyleDialog	Creates the older style of file-selection dialog.
ofNoDereferenceLinks	Disables dereferencing of Windows shortcuts. If the user selects a shortcut, assigns to FileName the path and file name of the shortcut itself (the .LNK file), rather than the file linked to the shortcut.
ofEnableIncludeNotify	(Windows 2000 and later.) Sends CDN_INCLUDEITEM notification messages to the dialog when the user opens a folder. A notification is sent for each item in the newly opened folder. You can use these messages to control which items appear in the folder's item list.
ofEnableSizing	(Windows 98 and later) Lets the Explorer-style dialog be resized with the mouse or keyboard. By default, the dialog allows this resizing regardless of the value of this option. It is only required if you provide a hook procedure or custom template. (Old style dialogs never permit resizing.)
ofDontAddToRecent	Prevents the file from being added to the list of recently opened files.
ofForceShowHidden	Ensures that hidden files are visible in the dialog.

C++ Examples:

Copy Code

/*
The following code allows the user to use a dialog box to
redefine the icon for the application at run time. When the
user clicks Button1, OpenDialog1 executes and the user
specifies an icon filename. The Icon is then assigned to the
application.  At runtime, click Button1 to select the icon,
then minimize the application to see the icon.
*/
void __fastcall TForm1::Button1Click(TObject *Sender)
{
  OpenPictureDialog1->DefaultExt = GraphicExtension(__classid(TIcon));
  OpenPictureDialog1->FileName = GraphicFileMask(__classid(TIcon));
  OpenPictureDialog1->Filter = GraphicFilter(__classid(TIcon));
  OpenPictureDialog1->Options.Clear();
  OpenPictureDialog1->Options << ofFileMustExist << ofHideReadOnly << ofNoChangeDir;
  while (true)
  {
    if (OpenPictureDialog1->Execute())
    {
      if (!OpenPictureDialog1->Options.Contains(ofExtensionDifferent))
      {
        Application->Icon->LoadFromFile(OpenPictureDialog1->FileName);
        break;
      }
      else // reset Options to remove ofExtensionDifferent
      {
        OpenPictureDialog1->Options.Clear();
        OpenPictureDialog1->Options << ofFileMustExist << ofHideReadOnly << ofNoChangeDir;
      }
    }
    else // user cancelled
      break;
  }
}

Delphi Examples:

Copy Code

{
The following code allows the user to use a dialog box to
redefine the icon for the application at run time. When the
user clicks Button1, OpenDialog1 executes and the user
specifies an icon filename. The Icon is then assigned to the
application.  At runtime, click Button1 to select the icon,
then minimize the application to see the icon.
}
procedure TForm1.Button1Click(Sender: TObject);
var 
Done: Boolean;
filenamestring : String;
begin
  OpenPictureDialog1.DefaultExt := GraphicExtension(TIcon);
  filenamestring := GraphicFileMask(TIcon);
  OpenPictureDialog1.FileName := filenamestring;
  OpenPictureDialog1.Filter := GraphicFilter(TIcon);
  OpenPictureDialog1.Options := [ ofFileMustExist, ofHideReadOnly, ofNoChangeDir ];
  Done := False;
  while not Done do
  begin
  if OpenPictureDialog1.Execute then
    begin
    if not (ofExtensionDifferent in OpenPictureDialog1.Options) then
      begin
      Application.Icon.LoadFromFile(OpenPictureDialog1.FileName);
      Done := True;
      end
    else
//      OpenPictureDialog1.Options := OpenPictureDialog1.Options - ofExtensionDifferent;
    end
  else { User cancelled }
    Done := True;
  end;
end;

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