FIELD.TPU
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FIELD.TPU is the Turbo Pascal unit obtained by compiling FIELD.PAS. Turbo
Pascal units are explained in chapter 4 of the language manual for version 4.
FIELD.PAS was developed from KEYIN.INC by Michael H. Hughes so many of the
coding ideas in FIELD.PAS are his; however, FIELD.PAS incorporates
significant changes.

The main function in KEYIN.INC was called keyin. This function located each
field on the screen, allowed data entry to and editing of the field, and on
termination returned the number of the next field to be processed. The data
entered was stored in a string or an array. The main function in FIELD.PAS
is called editfield. Like keyin it locates each field on the screen and
allows data entry to and editing of the field, but it returns the key code of
the terminating key rather than the number the next field. As can be seen in
the demonstration programs, this allows construction of more elaborate
screens. Both vertical and horizontal tabing from field to field may be
programmed for editing but suppressed during initial data entry. Data can
still be stored in strings, but numbers can now be stored as variables.

OLDDEMO.PAS is the original demonstration program TESTKEY.PAS recoded to use
the new unit. Certain keying errors could spoil the screen of the old
program. The new program appears to be bullet proof.

NEWDENO.PAS is a simple chemical engineering program that illustrates how to
use FIELD.TPU to create a screen with a large number of fields that have the
same format. This screen style is required for many chemical engineering
problems.

FLDTEST.PAS was written to help debug FIELD.PAS. By playing with this
program you will get a good idea how the unit works.

Hopefully these demonstration programs and the comments in the source code of
the unit will allow interested programmers to use this unit without undue
pain.

Frank Wood, Jr.

CIS User ID 74375,127

July 2, 1988