To add help to your application, you specify either (1) a help string or (2) a help keyword for each field, choice list, scrollable region, data form, and menu for which you want to provide on-line help.
The help memory file is a file created using the Vermont Views memory file facility. It contains the help text for your application. The help memory file can be read in from an ASCII text file that you have created with any editor. Only one help memory file is active at a time. You do not need to know the details about memory files to use them to create help text.
You can implement a help system for your application that uses only help strings, only help keywords and a memory file, or a combination of the two methods.
If you use only help strings throughout your application, you do not need to create an ASCII help text file or use a help memory file. The amount of help information you can provide in a help string is limited to the size of the help window. Furthermore, any changes to the help information must be made in your application's source code; in the case of Designer forms, changes can be made to the help string information specified for the form using the Designer.
If you use help keywords, you can create an ASCII file containing help text for each keyword and read and process that file in your application. Using a text file allows you to provide complete scrollable help for your applications. The help information in the ASCII text file can easily be modified using any text editor.
How to implement both types of help is described in detail later in this chapter.
