ind1cator_arg

EXAMPLES:

INDICATOR _pass

_fall

_{new old} change

See _{the chapter} on INDICATORs for more information.

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C-8 ELEMENTS OF CONFIGURATIONS _{DataFlex 2.0 User's} Manual

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DEa-ARINg DATA ELEMENTS

::::Z

_--

——— ~ ~~

========== ———————

—————— There are five DataFlex Definition Commands:

STRING NUI¶3ER DATE INTEGER INDICATOR

They _{serve to provide the configurator with} a means of identifying typed variables to the DataFlex compiler. Once _{identified, the}

variable argument can be used _at

_will

_{throughout the configuration.} The _definition comnand which _establishes a variable must precede _the

first

use of the variable in a given configuration.

FORMAT:

COMMAND var1ab1e_arg EXAMPLE:

STRING keyboard_1nput

The

_first

_{three definition} comands _{support the three} data _types which can be _{defined in} a DataFlex

file

structure: ASCII _strings, numbers

(stored as packed BCD), and dates (Julian _{- stored} as packed BCD numbers). In _the case of the NUMERIC and DATE connands9 up to nine

(9) _variables can be _defined on a _single comand _line. STRING Command

If

the maximum _{string length is not} spéc1f"fédo _{a default} maximum

length of 80 _{characters is} assigned by _DataFlex. Use _{of defined}

string space is not dynamically allocated in memory; therefore, length specification can significantly conserve memory utilization. Strings consume _{their defined length plus} 2 _{bytes in} memory. The

allowable range for string length specification is from _{I to} 255

characters.

FORMAT:

STRING variab1e_name _{{string length}}

C-lO DECLARING DATA ELEMENTS _DataFlex 2.0 _User's Manual

EXAMPLES:

STRING _{flag I} STRING response STRING my_entry lOó

The _{string variables} HÁG$ RESPONSE, and MY_EN1RY are declared for a DataFlex configuration by the above commands. FLAG is

defined to one (I) character. RESPONSE _{is defined to eighty} (BO) _characters by _default, and MY_ENTRY _{is defined to} a

length of one hundred (LOO) _characters.

If

entry is subsequently made _to a string variable which exceeds _the

declared length of the variable, excess input

_will

be _discardecb such as:

STRING code 3 MOVE "ABCDE" TO code

CODE _{will not contain} ABCDE.

_{It will}

_{contain only the}

_first

3

characters, ABC. No _{error will} be _{declared unless} one is provided for the condition in the configuration.

NUMBER Command

Multiple numeric _variable arguments can be defined on a single definition line. The _variable names must be _separated by spaces. FORMAT:

NUMBER variab1e_namel variab7e_name2

...

variab1e_namen

EXAMPLES:

NUMBER _quantity

NUMBER amount_due _credit

NIM3ER area_code phone_exchange phone_number

A NUMBER _variable consumes 10 _{bytes of} memoryp and has a _{value of zero}

automatically when

it

is declared.

_If

there is sufficient m«nory for storing them DataF1ex can manage up to 32g767 _active NUMBER _variables

at one time. The range of numbers _{in DataFlex is:} + _{or - 99,999.999.99%999.9999}

"

DATE Command

Mu1tip1e _{date variable} arguments can be _defined on a single comand

line. FORMAT: DATE _{date_argl}

...

date_argn EXAMPLES: DATE _{invo1ce_date}

DATE due_date _{ffrst_reminder} second_reminder

=,=~~———~~————~—"" =

_"""""

DataFlex 2.0 _User's Manual DECLARING DATA ELEMENTS _C-ll

_—— —————

————.

INTEGER Command

The INTEGER command _{allows the creation of} a memory _{variable to}

contain an integer value.

_It

differs from _the NUMERIC _{variable in}

that the INTEGER _variable consimes less mmory for storagep anch _of

course, does _{not support fractional} accuracy in calculations.

However, _{the greatest value of integers in corifigurations is} when they are used _{for counters, in} FOR 1oopsp and _{with the} INCREMENT command. Some _{pre-defined integers provide} access _{to DataFlex systan variables}

(e.g. ERRLINE = the last error line).

The range available for Integers is plus or minus 327767. There _is no INTEGER _{storage type in the} data base; _all numbers _{are stored on disk} as binary.coded decimals (BCD). In memoryg however, a NUMBER data

element constnes ID bytesp while an INTEGER data element _{occupies only} 2 _bytes. FORMAT: INTEGER _argumentl

...

argumentN EXAMPLES: INTEGER my_age

INTEGER qty_so1d _{qty_returned qty_shipped}

Integer variables are stored in an internal array in the order in

which _they are declared. When _the DataF1ex CHAIN connand _{is execute6}

the integer _{array is jiQt reinitialized.} This provides the

_facility

_to pass integer values from one configuration to another without writing

the values to a

file.

The _{internal integer array is sequentially allocated} as the variables

are declared. Thereforeg

if it

is desired to pass integer values in

QiAINed _{configurations,} we suggest _{that the} same integer names be

declared at the beginning of each _{configuration to provide for} a

consistency in variable referencing. When _integer values are not

passed between _{configurations, they} should be _{initialized before} use. EXAMPLE:

MOVE O TO sheep_counter

_//

_inlt1alize sheep_counter

————————————————

C-12 DECLARING DATA ELEMENTS DataF7ex _{2.0 User's} Manual

——

————

INDICATOR Command

The INDICATOR _definition command _defines a special type of DataFlex

argument which _is used _{for conditional processing} and program control.

The INDICATOR comíand _creates an "Indicator".

The named _{indicator established} as the argument _{of the} INDICATOR command _takes on the characteristics of a "flag" which _{is tested} by

the configuration to determine whether _a cormand _{line or} group is to

be _{executed. Indicators} are discussed

_fully

in the section on

"Conditional Execution".

FORMAT:

INDICATOR _{ind1cator_arg}

==—————~—————~ """"""""""===————— C"l3 —— —_{—————} ~~~~

—————————— ——————————

========== MANIFULATING DATA ELEKNTS ==========

=========~~~—————————————————————————— ——————————— =

——————————— MOVE Command

MOVE _{provides the}

_facility

_{to "transport" data throughout} a DataFlex application without regard _{for the type or location of the} source _or

destination arguments. Data can be MOVEd from window _to window» window _to data base _"e1ment"» element _to windowp element _{to e1%entp}

expression to window _or e1emeñt» _{etc.p etc.} Where _{expressions are}

part of the MOVE connandp _{they will} be _{automatica1ly evaluated with}

the result being MOVEd _{to the destination} argument. _Further. any

required type conversions will also be executed _{automatically.} FORMAT:

MOVE _{source_var} TO _{dest1nat1on_var} EXAMPLES:

MOVE _"DataFlex" TO _{str1ng_arg} MOVE _06/01/83 TO _{date_arg} MOVE _(invt.qty

-

qty_ordered) TO invt.qty

MOVE _screen.date TO lnvo1ce_date

_//

_then... MOVE _{(invoice_date} + 30) TO _invoice.due

The MOVE command decodes _{the type of the destination variable} and

internally generates one of the _{fOllowing types of} move commands _for

the comnand _processor: MOVENUM _for numbers MOVEINT _{for integers} MOVESTR _{for strings}

Neither variable may be a _{label or indicator.} While _the source may be a

literal

string _or numbem the destination variable may not be. The MOVE command _{will not} update _{accumulators in the} SUBTOTAL _{section of}

the REPORT macro. See _the PRINT command _{for this} purpose.

C-14 MANIPULATING DATA ELEMENTS _DataFlex 2.0 _User's Manual

INCREMENT Command

The INCREMENT comand _operates on an integer variable, and _is used as a counter for loops and repetitive operations. Literals, 1abelm and

indicators may not be used _{in this} command.

_It

_{incrwents only} by _the

integer

_I.

FORMAT:

INCREMENT _{fnteger_var}

This comnand _{is equivalent to:}

MOVE _{('lnteger_var} + _I) TO _{integer_var}

...but is faster in operation.

—————— CALCULATE Command

The CALCULATE comnand _is used _{to evaluate} an expression and move the result to a destination variable of the numeric _type. When _{using the} CALCULATE comand you must _determine

_if

_{the destination} argument _{is of}

the numeric _type.

_If

you _{are not sure,} use the MOVE connand _instead. MOVE can also evaluate expressions.

An _{abbreviation of the} CALCULATE commanch "CALC" can be used _inter- changeably _{with the}

_full

comnand word.

FORMAT:

CALC{ULATE} _{expressfon_arg} TO _{destinat1on_var} EXAMPLES:

CALWLATE (12+6) TO g_tota1

CALC _{(date_ord+cust.tems)} TO _{invo1ce.date_due} CALC _(3.14*66.4) TO area

The _{destination variable} may not be a label. indicatorp constantg or

ASCII _variable.

_It

may be an integer9 numer1cg _{or date variable.} The CALCULATE comnand _{will not} update _{accumulators in the} SUBTOTAL _section

of the REPORT macro. See the PRINT command for this purpose.

—————-.————

~ ~—~~—_~———~—__~======"="="===== CR 5

==-==:_::

DATA ENTRY =-EFE=-==-

"=""====== ——~— —~ —~ ———— ——~~———~——~~———~======= ——————————————————————————

Application requirements for data _entryp

_file

maintenance and

_file

inquiry, are efficiently met by _{the DataFlex} ENTER command macro. ENTER _provides a complete program skeleton for data _{entry using} IMAGE

formats and _Flex-keys. The ENTER _{macro can handle multi pIe rel}a'ted f11esp

_file

update proceduresp _{transaction creation} and _online

editing. There _{are user-defined procedures for specific operations} so

the user can set up whatever auxiliary update procedures and error

trapping may be _required.

Since connand macros _{are stand-alone} program skeletons, they can only

be used once in a configuration. Specl

f

ic connand _{statements are} used

within and around _the command macros to provide functions to

accommodate a variety of requirements.

The ENTER comand _{invokes the} ENTER macro, which _{is in fact} an entire group of processing routines that perform the following functions:

l.

ENTER data _via CRT screen images, _{with validation,}

type checking, range checking and _{error trapping.}

2. CREATE _{records in the} data base _with data _{entered through}

the screen imagep and _{in the} process» update related data base _records, key _{iMéxésó etc.» all} without having _to

create routines and procedures _for such _activities.

3. FIND data _{in the} data base by key _field and _display

it

on

the formatted CRT _{"image". Single records or multiple}

related records can be _{"found" with} a single key _stroke. Data can then be _inspected, scannéd» _{"edited, deleted.}

4. EDIT _{existing records in the} data base and _{in the process,}

properly update _related data base _records, key indexesD

etc. without custom _routines and _procedures. 5

. DELETE records from the data base while processing

all

required updates _on-line.

6. CLEAR _displayed data from the screen image.

~ ~

————

C-16 DATA ENTRY _DataFlex 2.0 _User's Manual

=="·="'="'=

The _{operation of the} ENTER command macro assumes that the database

fijes

dealt with have _previously been _{defined with the DataFlex} FILEDEF _or AUTODEF

_utilities.

Mu1tipie records from _different database

_files

can be _{displayed with} ease and _f1exibi11ty by _the ENTER macro. However. _{the structure of}

the ENTER comnand does impose _{the limitation that only} one record from a given data

Íile

may be _displayed on the screen at one time.

_It

will not, for example, _support a multi-item format like an invoice. Con-

figurations requiring mu1ti-1ine formats should be "programmed" _with-

out the use of the ENTER macro. The ENTERGROUP comand _{is useful} In

applications requiring multi-line formatting. See _the INVOICE.FRM demo

_file

_for an example _of a programmed mu1ti-1ine (non-ENTER)

configuration.

A _specific command _{structure is} used _{with the} ENTER macrog and _there are a series of optional comnands designed _{to control the formatting} and _actions which

occur within the data windows of the screen image.

Configuration examples _{at the} end _{of this chapter} can serve as a

useful guide _{during the discussion of} these coimands.

————————————

DataFlex 2.0 _User's Manual DATA ENTRY C-17

ENTER CONFIGURATION STRUCTURE:

//

IMAGE SECTION

---

lpagenamel

_//

_start image _section

---- first

page of image

---

/pagename2

_//

can have _multiple images

----

following pages of image

---

l*

//

end _of image _section

//

PRE- ENTER COMMAND SECTION

""--

OPEN _f11el

_//

open all

files

and

OPEN _f1le2

_{// initialize}

any variables used and

//

give window _formatting commands

//

"""___"____ INVOKE ENTER MACRO USING ENTER COMMAND

----

="="

ENTER

_filel

_fi1e2

_//

_start ENTER _mini program

//

declare related

_files

In order:

//

"senior" to "junior"

//

= ENTRY SECTION _______"___

AUTOPAGE page

//

AUTOPAGE required only for

//

second and _following screens EN7RY _{field {windjw} {options}}

ENTRY

In document DataFlex V2 Jul1984 pdf (Page 119-129)