Graphics.GraphicFileMask Function

Returns a file mask that specifies the valid extensions for a graphic class.

Pascal

function GraphicFileMask(GraphicClass: TGraphicClass): string;

C++

AnsiString GraphicFileMask(TGraphicClass GraphicClass);

File

Graphics

Description

Call GraphicFileMask to obtain a mask to determine the file extensions associated with a graphic class. The GraphicClass parameter can specify one of these values: TBitmap, TGraphic, TIcon, TMetafile, or a user-defined descendant of TGraphic. These are the strings that are returned for each built-in graphics class:

Graphic class	Filter string returned
TBitmap	*.bmp
TIcon	*.ico
TMetafile	.emf;.wmf
TGraphic	.bmp;.ico;.emf;.wmf
TGraphic	;.bmp;.png;.xpm.ico

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;