Example
The CASE-statement is a lot more strict than the IF/ELSE-conditional. It can only compare a single variable and only equality, not larget/smaller than etc.
DEFINE VARIABLE c AS CHARACTER NO-UNDO.
CASE c:
WHEN "A" THEN DO:
RUN procedureA.
END.
WHEN "B" THEN DO:
RUN procedureB.
END.
OTHERWISE DO:
RUN procedureX.
END.
END CASE.
Using an OR each WHEN can compare different values:
DEFINE VARIABLE c AS CHARACTER NO-UNDO.
CASE c:
WHEN "A" THEN DO:
RUN procedureA.
END.
WHEN "B" OR WHEN "C" THEN DO:
RUN procedureB-C.
END.
OTHERWISE DO:
RUN procedureX.
END.
END CASE.
Just like with the IF-statement each branch can either be a single statement or a block. Just like with the ELSE-statement, OTHERWISE is not mandatory.
DEFINE VARIABLE c AS CHARACTER NO-UNDO.
CASE c:
WHEN "A" THEN
RUN procedureA.
WHEN "B" OR WHEN "C" THEN
RUN procedureB-C.
END CASE.
Unlike a c-style switch-clause there's no need to escape the CASE-statement - only one branch will be executed. If several WHENs match only the first one will trigger. OTHERWISE must be last and will only trigger if none of the branches above match.
DEFINE VARIABLE c AS CHARACTER NO-UNDO.
c = "A".
CASE c:
WHEN "A" THEN
MESSAGE "A" VIEW-AS ALERT-BOX. //Only "A" will be messaged
WHEN "A" OR WHEN "C" THEN
MESSAGE "A or C" VIEW-AS ALERT-BOX.
END CASE.
