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Using ACCEPT and DISPLAY Statements for Input/Output and Video Forms
11.3 Designing Video Forms with Screen Section ACCEPT and DISPLAY
Table 11–5 Color Table
Color Color Value Color Color Value
Black 0 Red 4
Blue 1 Magenta 5
Green 2 Yellow/Brown 6
Cyan 3 White 7
11.3.1.1 Comparison of Screen Section Extensions with Other Extensions of ACCEPT and
DISPLAY
This section points out some of the major differences and similarities between the
Screen Section and non-Screen Section extensions to help you determine which to
use.
Similarities
There are significant similarities between the Screen Section feature and that of
the non-Screen Section screen formats, as follows:
• You can clear part or all of your screen as you DISPLAY a screen. Each
output screen item within a screen description entry can specify an ERASE
option.
• With all formats, if you do not specify the initial cursor position, by default it
will be at the upper left corner of the screen — screen coordinates (1,1), first
line, first column.
• Each screen item within a screen description entry can specify a line and
column position. If the line and column are not specified for a screen item,
then the screen item begins immediately following the previous screen item.
Regardless of whether you display or accept the entire screen or only part of
the screen, the positioning of each screen item remains the same.
• If you display escape or control sequences within a screen description entry,
you need to use absolute cursor positioning to get predictable results.
In a number of cases, a clause that you can use in the Screen Section of the
Data Division, in the screen description entry, accomplishes the same purpose
as a clause in the Procedure Division’s ACCEPT or DISPLAY statement (in a
non-Screen Section extended format). The difference is in the clauses’ names
(not interchangeable) and where you use them: in the Data Division’s Screen
Section, or in the Procedure Division with the ACCEPT or DISPLAY statement.
The following table shows these clauses:
Screen Section Clause ACCEPT or DISPLAY Clause with Equivalent Effect
AUTO AUTOTERMINATE
BLANK LINE ERASE LINE
BLANK SCREEN ERASE SCREEN
BLINK WITH BLINKING
ERASE EOL ERASE TO END OF LINE
ERASE EOS ERASE TO END OF SCREEN
HIGHLIGHT BOLD
11–34 Using ACCEPT and DISPLAY Statements for Input/Output and Video Forms