Declaration: SelectFile(InitialDir, Filter, Caption: string): string;
Opens the Windows file selection dialog. The parameter InitialDir controls the directory which is initially displayed. Assigning an empty string to this parameter forces the open dialog to show the working directory of Epina ImageLab. The Filter parameter is a sort of wildcard filter to narrow down the visible files (for example, assigning '*.ilab' only shows Epina ImageLab data files, or '*.*' shows all available files). The function returns the file specification (including the full path) of the selected file, or an empty string if the file selection dialog has been cancelled. The Caption parameter determines the text in the title bar of the dialog.