【IT168 技术文章】
Full type specification
REPORT demo_field_symbols_type .
DATA: BEGIN OF line,
col1(1) TYPE c,
col2(1) TYPE c VALUE 'X',
END OF line.
FIELD-SYMBOLS <fs> LIKE line.
ASSIGN line TO <fs>.
MOVE <fs>-col2 TO <fs>-col1.
WRITE: <fs>-col1, <fs>-col2.
DATA: BEGIN OF line,
col1(1) TYPE c,
col2(1) TYPE c VALUE 'X',
END OF line.
FIELD-SYMBOLS <fs> LIKE line.
ASSIGN line TO <fs>.
MOVE <fs>-col2 TO <fs>-col1.
WRITE: <fs>-col1, <fs>-col2.
--------------------------------------------------------------------------------
Forcing structures
REPORT demo_field_symbols_structure .
DATA: wa(10) TYPE c VALUE '0123456789'.
DATA: BEGIN OF line1,
col1(3) TYPE c,
col2(2) TYPE c,
col3(5) TYPE c,
END OF line1.
DATA: BEGIN OF line2,
col1(2) TYPE c,
col2 TYPE sy-datum,
END OF line2.
* obsolete -------------------------------------------------------------
FIELD-SYMBOLS: <f1> STRUCTURE line1 DEFAULT wa,
<f2> STRUCTURE line2 DEFAULT wa.
* correct --------------------------------------------------------------
FIELD-SYMBOLS <f3> LIKE line1.
ASSIGN wa TO <f3> CASTING.
FIELD-SYMBOLS <f4> LIKE line2.
ASSIGN wa TO <f4> CASTING.
* ----------------------------------------------------------------------
WRITE: / <f1>-col1, <f1>-col2, <f1>-col3,
/ <f2>-col1, <f2>-col2.
SKIP.
WRITE: / <f3>-col1, <f3>-col2, <f3>-col3,
/ <f4>-col1, <f4>-col2.
DATA: wa(10) TYPE c VALUE '0123456789'.
DATA: BEGIN OF line1,
col1(3) TYPE c,
col2(2) TYPE c,
col3(5) TYPE c,
END OF line1.
DATA: BEGIN OF line2,
col1(2) TYPE c,
col2 TYPE sy-datum,
END OF line2.
* obsolete -------------------------------------------------------------
FIELD-SYMBOLS: <f1> STRUCTURE line1 DEFAULT wa,
<f2> STRUCTURE line2 DEFAULT wa.
* correct --------------------------------------------------------------
FIELD-SYMBOLS <f3> LIKE line1.
ASSIGN wa TO <f3> CASTING.
FIELD-SYMBOLS <f4> LIKE line2.
ASSIGN wa TO <f4> CASTING.
* ----------------------------------------------------------------------
WRITE: / <f1>-col1, <f1>-col2, <f1>-col3,
/ <f2>-col1, <f2>-col2.
SKIP.
WRITE: / <f3>-col1, <f3>-col2, <f3>-col3,
/ <f4>-col1, <f4>-col2.
--------------------------------------------------------------------------------
Static assign
REPORT demo_field_symbols_stat_assign .
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>.
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>.
