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SELECT CASE

Evaluates an expression and executes the corresponding block of statements.

Syntax

SELECT CASE test_expression CASE match_expression [ statements] [ CASE match_expression [ statements]] … [ CASE ELSE [ default_statements]] END SELECT

Comments

The SELECT CASE statement evaluates an expression and searches the list of possible cases for a match. If a match is found, QBasic executes the statements for that case.

test_expression is a string or numeric expression to evaluate and compare to the possible cases.

match_expression is an expression to match test_expression. It can have the form

expression[, expression]…

If any of the expressions listed match test_expression, statements executes.

match_expression can also take the form

expression TO expression

This provides a range of possible values to match.

Lastly, match_expression can have the form

IS relation_operator expression

where relation_operator is <, >, <=, >=, =, or < >.

statements is the list of statements that execute for a matching case.

default_statements is the list of statements that execute when no matching expression is found. These statements are associated with the CASE ELSE clause.

After the statements within a matching case execute, the program continues execution at the first statement following the END SELECT statement.

Example

FOR i = 1 TO 5 
  SELECT CASE i 
    CASE 1
      PRINT "One"
    CASE 2, 3
      PRINT "Two or three"
    CASE IS = 4
      PRINT "Four"
    CASE ELSE
      PRINT "Five"
  END SELECT
NEXT

Results in:

One
Two or three
Two or three
Four
Five

See Also