Specifications

319
Syntax:
SELECT conditionalexpression
CASE test1
[statementblock]
[CASE test2
[statementblock]]...
[CASE ELSE
[statementblock]]
END SELECT
Parameter:
conditionalexpression, test1, and test2
A numeric or string expression.
Description:
This statement executes one of statementblocks depending upon the value of
conditionalexpression according to the steps below.
(1) SELECT evaluates conditionalexpression and compares it with
tests sequentially to look for a match.
(2) When a match is found, the associated
statementblock executes and
then control passes to the first statement following the END SELECT.
If no match is found, the
statementblock following the CASE ELSE exe-
cutes and then control passes to the first statement following the END SELECT.
If you include no CASE ELSE, control passes to the first statement following the
END SELECT.
• If the SELECT statement block includes more than one CASE statement contain-
ing the same value of
test, only the first CASE statement executes and then
control passes to the first statement following the END SELECT.
• If a
CASE followed by no executable statement is encountered, control passes to
the first statement following the END SELECT.
•
conditionalexpression (numeric or string) and tests must agree in
type.
Flow control statement
SELECT...CASE...END SELECT
Conditionally executes one of statement blocks depending upon the value of an expression.