Owner`s manual

25
The random access file prepared in that way would be as follows. If product no.
K=12, 5 data are registered in elements corresponding to array expressions
56 - 60.
Data position
a expression
~
KJl:5-4} 55
___ 56
K=12 57
58
59
60
61
N$
p
S
T
C$
d
ata
..... product name
..... unit price
..... inventory count
..... total amount
..... comment
BRD file
"STORE LIST"
In this way, then, data can be set in any specified array in the file. As a result, unlike
the sequential access file, in which data is overlaid in
order from the heading, it is also
possible for there to be vacant addresses in the filed data.
And, because data can be accessed
at will, it is also possible to easily rewrite data.
Use the practice problem to become accustomed to the use of the BRD file.
Problem
Let's read-out the random access file
"STORE LIST" made here and read-out the
inventory data for a certain product.
The program execution
is ended, however, when "0" is input.
Read out
of inventory data
500 XOPEN #7, "STORE LI ST"
5 1 0
520
530
INPUT
INPUT
PRI NT
" pro d u c t no. ="; J : I F J =0 THE N 700
#7( J*5-4), N$, P, S, T, C$
" NO. "; J : PR I NT "p rod u c t n a me "; N$
540 PR I NT "u n i
price ";P
550 PRI NT "i nventory count" S
560 PR I NT "t 0 t a I a mo u n t "; T
5 7
0 P R I N T "c 0 mme n t "; C $
580 GOTO 510
700 CLOSE #7
710 E NO
In this way then, even for many products, the inventory data can be quickly read-out
by inputting the product number.