Editing Field (Columns 45 Through 80); Check(Dd) - IBM 5280 Programmer's Manual

Both Input and Output (B) Fields
The literal appears on the screen when your COBOL program issues an
associated WRITE statement. The use of literals is shown at
II
through
D
in Figure 2.5 earlier in this chapter.
3. You must leave the Field Name field (columns 19-24 of the field
description statement) blank.
For those fields defined for both input and output (you enter a B in the Usage
field):
1. The operator can enter data on the screen in fields defined by the
statements.
2. The operator can duplicate data from the corresponding positions in the
preceding record by pressing the Duplicate key, unless you specify
CHECK(DD) as explained later in this section.
3. Data can be automatically duplicated in the field when the the operator has
pressed the Auto Dup/Skip key, and you have coded the CHECK(AD)
keyword and parameter in the editing field of the associated field
description statement. The data is automatically duplicated from the
corresponding positions in the previous record when the cursor enters the
field.
When using a field for both input and output, consider the following when
writing your COBOL program:
1. The field description statements with a B specified in the Usage field define
02 level elementary items in the COBOL program.
2. When a WRITE is executed, any data in the associated record will be
written to the screen. You should therefore ensure that such fields are
either initialized with blanks or the data you want before the WRITE is
executed.
3. The operator can write over any data appearing in the field.
To Prevent Entry of Data in a B-Field
To prevent the entry of data in a B- Field, use the CHECK(BY) keyword
described later in this chapter. With this keyword, you can cause the cursor to
bypass a field on the screen either conditionally or unconditionally.
Editing Field (Columns 45 through 80)
CHECK(DD)
The entry you make in the editing field applies to subordinate field statements
which don't contain overriding keywords in columns 45-80.
You can specify the fonowing keywords in a record description statement:
Keyword
CHECK
DSPATR
Description
Keyboard level edits
Display attributes
The CHECK(DD) keyword prevents the operator from using the DUP key for
fields defined by subordinate field description statements. If CHECK(DD) is
specified in the record description statement, you cannot override it in a
subordinate field description statement.
CHECK allows a wider range of edits when specified in the field description
statement, as described under "Field Description Statement" below.
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