Internal table containing field symbols (Guru question)

[Former Member]

Hi,

I wanted to create an internal table that contains an id and a field symbol.

something like:

types: begin of my_type,

id(2) type c,

field-symbols: <fs> type something.

end of my_type.

data: my_table type standard table of my_type,

wa type my_type.

wa-id = 'B'.

wa-fs = <fs_second>.

I know won't pass the checker, but I'd like to know if it was possible. I'm able to use references, but I want field symbols so I will avoid reading a huge table or create secondary indexes....

Thanks for the help,

Isidoro!

[former_member583013]

AFAIK you can't declare a Field-Symbols inside an Internal Table....

What you can do is declare a Field-Symbol to use only the header...like this....

TYPE: BEGIN OF TY_DATA,
           FIELD1 TYPE C,
           FIELD2 TYPE C,
           END OF TY_DATA.

DATA: DATA TYPE STANDARD TABLE OF TY_DATA WITH HEADER LINE.
FIELD-SYMBOLS: <DATA> LIKE LINE OF T_DATA.

LOOP AT T_DATA ASSIGNING <DATA>.
*Do something...
ENDLOOP.

Greetings,

Blag.

[Former Member]

Here is the with Example and explanation also ...

DATA: BEGIN OF LINE,
COL1 TYPE I VALUE '11',
COL2 TYPE I VALUE '22',
COL3 TYPE I VALUE '33',
END OF LINE.

DATA COMP(5) VALUE 'COL3'.

FIELD-SYMBOLS: <F1>, <F2>, <F3>.

ASSIGN LINE TO <F1>.
ASSIGN COMP TO <F2>.

DO 3 TIMES.
ASSIGN COMPONENT SY-INDEX OF STRUCTURE <F1> TO <F3>.
WRITE <F3>.
ENDDO.

ASSIGN COMPONENT <F2> OF STRUCTURE <F1> TO <F3>.
WRITE / <F3>.

The output is:

11 22 33

33

The field symbol <F1> points to the structure LINE, <F2> points to the field COMP. In the DO loop, the components of LINE are specified by their numbers and assigned one by one to <F3>. After the loop, the component COL3 of LINE is specified by its name and assigned to <F3>. Note that ASSIGN COMPONENT is the only possible method of addressing the components of <F1>. Expressions such as <F1>-COL1 are syntactically incorrect. The main thing is ASSIGN statement sets the sy-subrc.

i.e u can also write the DO loop as...

DO.
ASSIGN COMPONENT SY-INDEX OF STRUCTURE <F1> TO <F3>.
if sy-subrc ne 0.
exit.
endif.
WRITE <F3>.
ENDDO.

*******************************************

this is a simple use of the field symbols

*******************************************

FIELD-SYMBOLS: <f1> TYPE ANY, <f2> TYPE i.

DATA: text(20) TYPE c VALUE 'Hello, how are you?',
num TYPE i VALUE 5,
BEGIN OF line1,
col1 TYPE f VALUE '1.1e+10',
col2 TYPE i VALUE '1234',
END OF line1,
line2 LIKE line1.

ASSIGN text TO <f1>.
ASSIGN num TO <f2>.
DESCRIBE FIELD <f1> LENGTH <f2>.
WRITE: / <f1>, 'has length', num.

ASSIGN line1 TO <f1>.
ASSIGN line2-col2 TO <f2>.
MOVE <f1> TO line2.
ASSIGN 'LINE2-COL2 =' TO <f1>.
WRITE: / <f1>, <f2

>.

The output is:

Hello, how are you? has length 20

LINE-COL2 = 1,234

The example declares two field symbols <F1> and <F2>. <F2> has the type I, which means that only type I fields may be assigned to it. <F1> and <F2> both point to different fields during the program.

reward points if it is usefull ....

Girish

[rodrigo_paisante3]

Hi,

I made this class yesterday to a friend about generic type, maybe this can help you too.

*------ Class some_class definition

CLASS some_class DEFINITION.

PUBLIC SECTION.

METHODS write_dados.

METHODS manual_ins IMPORTING id TYPE scustom-id

name TYPE scustom-name date TYPE sy-datum.

METHODS add_values IMPORTING tabela TYPE any.

PRIVATE SECTION.

TYPES: BEGIN OF dados,

id TYPE scustom-id,

name TYPE scustom-name,

date TYPE sy-datum,

END OF dados.

DATA: t_dados TYPE TABLE OF dados.

ENDCLASS. "some_class DEFINITION

*------ class implementation

CLASS some_class IMPLEMENTATION.

*------ method add values

METHOD add_values.

FIELD-SYMBOLS: <wa> TYPE ANY,

<fstable> TYPE table.

ASSIGN tabela TO <fstable>.

LOOP AT <fstable> ASSIGNING <wa>.

APPEND <wa> TO t_dados.

ENDLOOP.

ENDMETHOD. "some_class

*------ method manual insert

METHOD manual_ins.

DATA: temp TYPE string.

FIELD-SYMBOLS: <wa> TYPE ANY,

<fstable> TYPE table.

ASSIGN t_dados TO <fstable>.

READ TABLE t_dados INDEX 1 ASSIGNING <wa>.

temp = <wa>.

<wa>+0(8) = id.

<wa>+8(25) = name.

<wa>+33(8) = date.

APPEND <wa> TO <fstable>.

<wa> = temp.

ENDMETHOD. "some_class

*------ method write dados

METHOD write_dados.

FIELD-SYMBOLS <wa> TYPE ANY.

LOOP AT t_dados ASSIGNING <wa>.

WRITE: / <wa>0(8), <wa>8(25), <wa>+33(8).

ENDLOOP.

ENDMETHOD. "some_class

ENDCLASS. "some_class IMPLEMENTATION

*------ program start

START-OF-SELECTION.

*------ vars

DATA: o TYPE REF TO some_class.

DATA: BEGIN OF ti_scustom OCCURS 0,

id LIKE scustom-id,

name LIKE scustom-name,

date LIKE sy-datum,

END OF ti_scustom.

CREATE OBJECT o.

SELECT id name FROM scustom INTO CORRESPONDING FIELDS OF ti_scustom.

ti_scustom-date = sy-datum.

APPEND ti_scustom.

ENDSELECT.

*------ add values of itab into class' itab

IF sy-subrc EQ 0.

CALL METHOD o->add_values( ti_scustom[] ).

ENDIF.

*------ insert the record manualy

CALL METHOD o->manual_ins

EXPORTING

id = 332

name = 'TESTE'

date = sy-datum.

*------ display the content of itab

CALL METHOD o->write_dados.

END-OF-SELECTION.

[former_member784222]

Hello,

You cannot have field symbols in internal table. But an alternate will be to have a data of type class 'DATA'. Verify the code below and let me know if it helps:

REPORT z_out.

TABLES: t001.

DATA: BEGIN OF itab OCCURS 0.
DATA: id TYPE i.
DATA: obj TYPE REF TO data.
DATA: END OF itab.

FIELD-SYMBOLS: <fs> TYPE ANY.
FIELD-SYMBOLS: <fs1> TYPE ANY.

itab-id = 1.
APPEND itab.

itab-id = 2.
APPEND itab.



LOOP AT itab.

  WRITE:/ itab-id.
  ULINE.
  CREATE DATA itab-obj LIKE t001.
  ASSIGN itab-obj->* TO <fs>.

  SELECT SINGLE * INTO <fs> FROM t001.

  DO.
    ASSIGN COMPONENT sy-index OF STRUCTURE <fs> TO <fs1>.
    IF sy-subrc = 0.
      WRITE: <fs1>.
    ELSE.
      EXIT.
    ENDIF.
  ENDDO.
  ULINE.
ENDLOOP.

Regards,

S. Chandra Mouli.