SAP OO OBS ON CHANGE 1

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ABAP Code Snippet
ARTICLE

ON CHANGE OF - ENDON not Permitted
The pseudo control structure ON CHANGE OF - ENDON is not permitted in ABAP Objects.

ABAP Objects error message at:

ON CHANGE OF f.
...
ENDON.

Correct syntax:

DATA g LIKE f.

IF f <(><<)>> g.
...
g = f.
ENDIF.

Reason:

The system internally creates a global invisible auxiliary field which cannot be controlled by the program. You are recommended to declare your own auxiliary field and process it with the IF control structure.