Sap script perform subroutine

Question

i got this sample code from sdn, but i have a dobt in this code.
here in form subroutine giving i_intpar and i_outpar i just wanted to know should we declare this structure before writing the subroutine,and what would be that structure
just explain this below code in detail,
pls help
Code this form routine in your script.
/: PERFORM GET_PYMT_DUE_IN IN PROGRAM ZSROINVOICE
/: USING &VBDKR-VBELN&
/: USING &VBDKR-FKDAT&
/: USING &VBDKR-ZTERM&
/: CHANGING &PYMNTDUE&
code it in ur driver program to fetch the details.
FORM get_pymt_due TABLES i_intpar STRUCTURE itcsy
i_outpar STRUCTURE itcsy.
DATA : wa_fkdat LIKE sy-datum,
wa_ztag2 LIKE t052-ztag2,
wa_pymnt LIKE sy-datum.
READ TABLE i_intpar WITH KEY name = 'VBDKR-FKDAT'.
IF sy-subrc = 0.
CONCATENATE i_intpar-value6(4) i_intpar-value3(2)
i_intpar-value+0(2)
INTO wa_fkdat.
ENDIF.
READ TABLE i_intpar WITH KEY name = 'VBDKR-ZTERM'.
IF sy-subrc = 0.
Payment Terms
SELECT SINGLE ztag2
INTO wa_ztag2
FROM t052
WHERE zterm = i_intpar-value.
ENDIF.
wa_pymnt = wa_fkdat + wa_ztag2.
MOVE 'PYMNTDUE' TO i_outpar-name.
CONCATENATE wa_pymnt6(2) '.' wa_pymnt4(2) '.' wa_pymnt+0(4) INTO
i_outpar-value.
APPEND i_outpar.
CLEAR i_outpar.
ENDFORM.
pls help

Answer 1

Hi
Hope it will help you.
Pls reward if help.
How to call a subroutine form SAPscripts
The Form :
/:PERFORM CDE_CENT IN PROGRAM ZKRPMM_PERFORM_Z1MEDRUCK
/:USING &EKKO-EBELN&
/:CHANGING &CDECENT&
/:ENDPERFORM
The report :
REPORT zkrpmm_perform_z1medruck .
DATA : BEGIN OF it_input_table OCCURS 10.
INCLUDE STRUCTURE itcsy.
DATA : END OF it_input_table.
déclaration de la table output_table contenant les
variables exportées
DATA : BEGIN OF it_output_table OCCURS 0.
INCLUDE STRUCTURE itcsy.
DATA : END OF it_output_table.
DATA : w_ebeln LIKE ekko-ebeln,
w_vbeln LIKE vbak-vbeln,
w_zcdffa LIKE vbak-zcdffa.
FORM CDE_CENT
FORM cde_cent TABLES input output.
it_input_table[] = input[].
it_output_table[] = output[].
READ TABLE it_input_table INDEX 1.
MOVE it_input_table-value TO w_ebeln.
CALL FUNCTION 'CONVERSION_EXIT_ALPHA_INPUT'
EXPORTING
input = w_ebeln
IMPORTING
output = w_ebeln.
SELECT SINGLE zcdffa FROM ekko
INTO w_zcdffa
WHERE ebeln = w_ebeln.
it_output_table-name = 'CDECENT'.
MOVE w_zcdffa TO it_output_table-value.
MODIFY it_output_table INDEX 1.
output[] = it_output_table[].
ENDFORM.
/: PERFORM
/: USING &INVAR1&
/: USING &INVAR2&
/: CHANGING &OUTVAR1&
/: CHANGING &OUTVAR2&
/: ENDPERFORM
INVAR1 and INVAR2 are variable symbols and may be of any of the four SAPscript symbol types.
OUTVAR1 and OUTVAR2 are local text symbols and must therefore be character strings.
Example:
In script form
/: PERFORM READ_TEXTS IN PROGRAM 'Z08M1_FORM_EKFORM1'
/: USING &EKKO-EKORG&
/: USING &EKPO-WERKS&
/: USING &EKKO-EKGRP&
/: USING &EKKO-BSTYP&
/: CHANGING &COMPNAME&
/: CHANGING &SENDADR&
/: CHANGING &INVCADR&
/: CHANGING &COMPADR&
/: CHANGING &COVERLTR&
/: CHANGING &SHIPADR&
/: CHANGING &REMINDER&
/: CHANGING &REJECTION&
/: CHANGING &POSTADR&
/: CHANGING &LOGO&
/: ENDPERFORM
In program
FORM Read_texts - To extract the standard texts from the table *
FORM READ_TEXTS TABLES IN_PAR STRUCTURE ITCSY
OUT_PAR STRUCTURE ITCSY.
DATA : L_EKORG TYPE EKORG,
L_WERKS TYPE WERKS_D,
L_BSTYP TYPE BSTYP,
L_EKGRP TYPE BKGRP.
READ TABLE IN_PAR WITH KEY 'EKKO-EKORG' .
CHECK SY-SUBRC = 0.
L_EKORG = IN_PAR-VALUE.
READ TABLE IN_PAR WITH KEY 'EKPO-WERKS' .
CHECK SY-SUBRC = 0.
L_WERKS = IN_PAR-VALUE.
READ TABLE IN_PAR WITH KEY 'EKKO-EKGRP' .
CHECK SY-SUBRC = 0.
L_EKGRP = IN_PAR-VALUE.
READ TABLE IN_PAR WITH KEY 'EKKO-BSTYP' .
CHECK SY-SUBRC = 0.
L_BSTYP = IN_PAR-VALUE.
CLEAR Z08M1_ORG_TEXTS.
SELECT SINGLE * FROM Z08M1_ORG_TEXTS WHERE EKORG = L_EKORG
AND WERKS = L_WERKS
AND EKGRP = L_EKGRP
AND BSTYP = L_BSTYP.
IF SY-SUBRC NE 0.
SELECT SINGLE * FROM Z08M1_ORG_TEXTS WHERE EKORG = L_EKORG
AND WERKS = L_WERKS
AND EKGRP = L_EKGRP
AND BSTYP = SPACE.
ENDIF.
READ TABLE OUT_PAR WITH KEY 'COMPNAME'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_COMP.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'SENDADR'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_ADRS.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'INVCADR'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_INVC.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'COMPADR'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_CPAD.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'COVERLTR'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_COVR.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'SHIPADR'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_SHIP.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'REMINDER'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_RMDR.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'REJECTION'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_RJCT.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'POSTADR'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_POST.
MODIFY OUT_PAR INDEX SY-TABIX.
READ TABLE OUT_PAR WITH KEY 'LOGO'.
OUT_PAR-VALUE = Z08M1_ORG_TEXTS-TXT_LOGO.
MODIFY OUT_PAR INDEX SY-TABIX.
ENDFORM.
REPORT ZMPO1 .
form get_freight tables in_par structure itcsy out_par structure itcsy.
tables: ekko,konv,t685t.
data: begin of itab occurs 0,
         ebeln like ekko-ebeln,
         knumv like ekko-knumv,
       end of itab.
data: begin of itab1 occurs 0,
         knumv like konv-knumv,
         kposn like konv-kposn,
         kschl like konv-kschl,
         kbetr like konv-kbetr,
         waers like konv-waers,
         kwert like konv-kwert,
       end of itab1.
data: begin of iout occurs 0,
         kschl like konv-kschl,
         vtext like t685t-vtext,
         kbetr like konv-kbetr,
         kwert like konv-kwert,
       end of iout.
data v_po like ekko-ebeln.
read table in_par with key 'EKKO-EBELN'.
if sy-subrc = 0.
   v_po = in_par-value.
   select
     ebeln
     knumv
  from ekko
  into table itab
  where ebeln = v_po.
  if sy-subrc = 0.
    loop at itab.
      select
        knumv
        kposn
        kschl
        kbetr
        waers
        kwert
      into table itab1
      from konv
      where knumv = itab-knumv and
            kappl = 'M'.
    endloop.
    loop at itab1.
      if itab1-kposn <> 0.
        select single * from t685t
                          where kschl = itab1-kschl
                            and kappl = 'M'
                            and spras = 'EN'.
        iout-vtext = t685t-vtext.
        iout-kschl = itab1-kschl.
        iout-kbetr = itab1-kbetr.
        iout-kwert = itab1-kwert.
        append iout.
        clear iout.
      endif.
    endloop.
    sort itab1 by kposn.
    loop at iout.
      sort iout by kschl.
      if ( iout-kschl eq 'GSDC' OR
           iout-kschl eq 'GSFR' OR
           iout-kschl eq 'GSIR' ).
        at end of kschl.
          read table iout index sy-tabix.
          sum.
         write:/ iout-kschl,iout-vtext,iout-kwert.
      out_par-name = 'A1'.
      out_par-value = iout-vtext.
      append out_par.
      out_par-name = 'A2'.
      out_par-value = iout-kwert.
      append out_par.
          endat.
        endif.
      endloop.
    endif.
  endif.
endform.
IN THE FORM I AM WRITING THIS CODE.
/:DEFINE &A1& = ' '
/:DEFINE &A2& = ' '
/:PERFORM GET_FREIGHT IN PROGRAM ZMFORM_PO1
/:USING &EKKO-EBELN&
/:CHANGING &A1&
/:CHANGING &A2&
/:ENDPERFORM
&A1&
&A2&
This Code is to be written in the PO form under ADDRESS window.
/:DEFINE &A1& = ' '
/:DEFINE &A2& = ' '
/:DEFINE &A3& = ' '
/:DEFINE &A4& = ' '
/:DEFINE &A5& = ' '
/:DEFINE &A6& = ' '
/:PERFORM GET_VENDOR IN PROGRAM ZMFORM_PO
/:USING &EKKO-EBELN&
/:CHANGING &A1&
/:CHANGING &A2&
/:CHANGING &A3&
/:CHANGING &A4&
/:CHANGING &A5&
/:CHANGING &A6&
/:ENDPERFORM
&A1&
&A2&
&A3&
&A4&
&A5&
&A6&