See Also: FileFilter Members
C# Example
public class MainWindow: Gtk.Window { protected virtual void OnBtnLoadFileClicked(object sender, System.EventArgs e) { Gtk.FileChooserDialog fc= new Gtk.FileChooserDialog("Choose the file to open", this, FileChooserAction.Open, Gtk.Stock.Cancel,ResponseType.Cancel, Gtk.Stock.Open,ResponseType.Accept); //filter begins here... FileFilter filter = new FileFilter(); filter.Name = "PNG and JPEG images"; filter.AddMimeType("image/png"); filter.AddPattern("*.png"); filter.AddMimeType("image/jpeg"); filter.AddPattern("*.jpg"); fc.AddFilter(filter); //second filter filter = new FileFilter(); filter.Name = "PNG Images (*.png)"; filter.AddMimeType("image/png"); filter.AddPattern("*.png"); fc.AddFilter(filter); //end filter code if (fc.Run() == (int)ResponseType.Accept) { System.Console.WriteLine } //Don't forget to call Destroy() or the FileChooserDialog window won't get closed. fc.Destroy(); }