Table of Contents

SELECT CASE

Executes one of several statement blocks depending on the value of an expression.

Syntax

SELECT CASE <expr>
  CASE <exp1> [, <exp2>, <exp3> ... ]
    <statements>
  CASE IS <relational operator> <exp4>  
    <statements>
  CASE <exp5> TO <exp6>
    <statements>
  CASE ELSE
    <statements>
END SELECT

In the first CASE block above, the value of <expr> is tested against <exp1>, <exp2> and <exp3> and the statement block is executed once one of them equals.

In the second block, a relational operator, <, <=, >, >=, <>, or = is provided and the statement block is executed if the relation evaluates to true. This works with numeric types only.

In the third block, the statement block is executed if <expr> is between <exp5> and <exp6> (inclusive). This works with numeric types only.

If one of the CASE expressions is tested to be true, the statement block will be executed and control will be passed to the code after END SELECT. That is to say, at most one statement block will be executed.

If none of the CASE expressions is tested to be true, control will be passed to CASE ELSE (if it exists).

Example

DIM a$ AS STRING * 3
again:
INPUT "your age? ";a$
age = VAL(a$)
SELECT CASE age
  CASE 0, 1
    PRINT "baby"
  CASE 2, 3
    PRINT "toddler"
  CASE 4 TO 10
    PRINT "child"
  CASE 11 TO 17
    PRINT "teenager"
  CASE IS >= 18
    PRINT "adult"
  CASE ELSE
    PRINT "invalid value"
    GOTO again
END SELECT

See also