| Form definitions / Form specification files | |
A form specification file is a source file that defines an application form, to let the end user interact with the program.
The form file defines the disposition, presentation (i.e. decoration), and behavior of screen elements called form items.
The source file must have the .per file extension: myform.per. Programs load the .42f compiled version of the form files, and use interactive instructions (dialogs) to control the form.
To compile a .per source file to a .42f format, use the fglform form compiler. When a SCHEMA is specified in the form file, fglform requires that the database schema files already exist. Compiled form files depend on both the source files and the database schema files.
Compiled forms will be loaded by the programs with the OPEN FORM or the OPEN WINDOW WITH FORM instructions. The FGLRESOURCEPATH environment variable must contain the directory where the compiled form files are located at runtime, if the form file is not in the current directory.
Once a form is loaded, the program can manipulate forms to display or let the user edit data, with interactive instructions such as INPUT or DISPLAY ARRAY. Program variables are used as display and/or input buffers.
The content of a .per form file must follow a specific syntax as described in Form file structure.