Sharp MZ-700 Owner's Manual page 57

2. 3. 6. 8
ON~GOSUB
............................... (abbreviated format:
ON~GOS.)
I
Format
I
ONe GOSUB Lr
1
<,
Lr
2 ,
Lr
3
, . . • . . ,
Lri
>
Function
Example
e . . . Numeric variable, array element, or expression
Lri . Destination line numbers
This statement branches execution to the subroutine beginning on one of the
line numbers following GOSUB, depending on the value of e. Operation of this
statement is basically the same as with the
ON~GOTO
statement, but
all
branches
are made to subroutines. Upon return from the subroutine, execution resumes
with the first executable statement following the ON~GOSUB statement which
made the call.
Let's try using the
ON~GOSUB
statement in a scheduling program. The most
important point to note in the following program is that, a subroutine call is made
· at line 180, even though line 180 itself is part of a subroutine (from line 170 to
190) which is called by line 90. Subroutines can be nested to many levels in this
manner.
10 A$= "
20 D$= "
30 G$= "
ENGL . " : B$= "
se
1 " :
E$= "
HI ST " : H$= "
MATH
MUS
ART
": C$= "
": F$= "
": I$= "
FREN
GYM
GEOG
40 0$= " BUS " :K$= " H RM " :PRINT "[!) "
50 INPUT "WHAT DAY'? " ;X$
60 FOR Z=1 TO 7:Y$=MID$C "S UNMONTUEWEDTHU
FR I SAT " . 1 +3::!<CZ-1 ), 3) : IF Y$ = X$ THEN X=Z
70 NEXT Z
80 FOR Y=0 TO 4:PRINT TAB C5 +6::!<Y);Y+1;
90 NE XT Y:PRINT
100 ON X GOSUB 180.120.130.140.150.1·60.170
110 PRINT:GOTO 50 ·
120 PRINT " MON ";A$; B$;D$;G$;K$:RETURN
130 PRINT " TUE "; B$;E$;H$;H$;D$:RETURN
140 PRINT " WED " ; C$; C$; I$; A$; F$ : RETURN
150 PRINT " THU " ;B$;D$;F$;G$;E$:RETURN
1 60 PRINT " FR I " ; A$; D$; I$ ; C$; C$ : RETURN
170 PRINT " SAT "; B$;G$;D$ ;K$:R ETURN
180 FOR Y=1 TO 6
1 9 0 ON Y GOSUB 1 20. 1 30. 1 40. 1 50. 1 60. 1 7 0
200 PRINT:NE XT Y
210 RETURN
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