Perform and Form statements

Question

Hello,
can anyone give egs of using PERFORM and FORM statement. what do these statements do actually.
thanks.

Answer 1

See this sample for PERFORM ... USING...CHANGING
DATA : c1 TYPE i, c2 TYPE i, res TYPE i.
c1 = 1.
c2 = 2.
<b>PERFORM sum USING c1 c2 CHANGING res.</b>
WRITE:/ res.
**& Form sum
** text
form sum using p_c1 p_c2 changing value(p_res).
p_res = p_c1 + p_c2.
endform. " sum
Note the difference between the above and below perform.
DATA : c1 TYPE i, c2 TYPE i, res TYPE i.
c1 = 1.
c2 = 2.
<b>data: subroutinename(3) VALUE 'SUM'.
PERFORM (subroutinename) IN PROGRAM Y_JJTEST1 USING c1 c2 CHANGING res</b>.
WRITE:/ res.
**& Form sum
text
form sum using p_c1 p_c2 changing value(p_res).
p_res = p_c1 + p_c2.
endform. " sum
ANother sample for simple perform
PERFORM HELP_ME.
FORM HELP_ME.
ENDFORM.
<b>... TABLES itab1 itab2 ...</b>
TYPES: BEGIN OF ITAB_TYPE,
         TEXT(50),
         NUMBER TYPE I,
       END OF ITAB_TYPE.
DATA:  ITAB TYPE STANDARD TABLE OF ITAB_TYPE WITH
                 NON-UNIQUE DEFAULT KEY INITIAL SIZE 100,
       BEGIN OF ITAB_LINE,
         TEXT(50),
         NUMBER TYPE I,
       END OF ITAB_LINE,
       STRUC like T005T.
PERFORM DISPLAY TABLES ITAB
                USING  STRUC.
FORM DISPLAY TABLES PAR_ITAB STRUCTURE ITAB_LINE
             USING  PAR      like      T005T.
  DATA: LOC_COMPARE LIKE PAR_ITAB-TEXT.
  WRITE: / PAR-LAND1, PAR-LANDX.
  LOOP AT PAR_ITAB WHERE TEXT = LOC_COMPARE.
  ENDLOOP.
ENDFORM.
Hope this helps.
Reward points if this helps u.