0 FIELD SYMBOLS IN ABAP

Field symbols:

Field symbols are placeholders or symbolic names for other fields. They do not physically reserve space for a field, but point to its contents. A field symbol can point to any data object. The data object to which a field symbol points is assigned to it after it has been declared in the program.

To declare a Field Symbol, use the statement,

FIELD-SYMBOLS <FS> [<type>|STRUCTURE <s> DEFAULT <wa>].

Typing  Field Symbols:

The <type> addition allows you to specify the type of a field symbol.

Syntax:

FIELD-SYMBOLS <FS> <type>

Ex :

*//variable declaration

      DATA: WA(10) VALUE '0123456789'.
DATA: BEGIN OF LINE1,
COL1(3),
COL2(2),
COL3(5),
END OF LINE1.

DATA: BEGIN OF LINE2,
COL1(2),
COL2 LIKE SY-DATUM,
END OF LINE2.
*//Field symbol declaration

FIELD-SYMBOLS: <F1> STRUCTURE LINE1 DEFAULT WA,
<F2> STRUCTURE LINE2 DEFAULT WA.

*//Display output      
WRITE: / <F1>-COL1, <F1>-COL2, <F1>-COL3,
/ <F2>-COL1, <F2>-COL2.

Output:

Static Assign:

The name of the data object you want to assign to a field symbol before run time.

Syntax:

           ASSIGN <f>  TO <FS>.

Ex:

*//Field symbol declaration

FIELD-SYMBOLS:  <F1> , <F2> TYPE I.

*//variable declaration
DATA : NUM  TYPE I VALUE 5,
      TEXT(10) TYPE C  VALUE 'HELLO'.
*//Static assign
      ASSIGN TEXT TO <F1>.
      ASSIGN NUM TO <F2>.

*//Display output      
      WRITE: / <F1> , <F2>. Output:

Dynamic  Assign:

The name of the data object you want to assign to a field symbol only at  run time.

Syntax:  ASSIGN (<f>)  TO <FS>.