Case

SELECT CASE value
    CASE testexp [[, testexp] …]
        <statements>
        <statements>
    CASE test-n [[, test-n] …]
        <statements>
        <statements>
    CASE ELSE
        <statements>
        <statements>
END SELECT

Executes one of several groups of statements, depending on the value of an expression.

value is the expression to be tested. It can be a number or string variable or a complex expression.

testexp (or test-n) is the value that is to be compared against. It can be:

A single expression to which it may equal
For example: 34, "string" or PIN(4)*5
A range of values in the form of two single expressions separated by the keyword TO
For example: 5 TO 9 or "aa" TO "cc"
A comparison starting with the keyword IS (which is optional). When a number of test expressions (separated by commas) are used the CASE statement will be true if any one of these tests evaluates to true.
For example: IS > 5, IS <= 10

When a number of test expressions (separated by commas) are used the CASE statement will be true if any one of these tests evaluates to true. If value cannot be matched with a testexp it will be automatically matched to the CASE ELSE. If CASE ELSE is not present the program will not execute any <statements> and continue with the code following the END SELECT. When a match is made the <statements> following the CASE statement will be executed until END SELECT or another CASE is encountered when the program will then continue with the code following the END SELECT.

An unlimited number of CASE statements can be used but there must be only one CASE ELSE and that should be the last before the END SELECT. Example:

SELECT CASE nbr%
    CASE 4, 9, 22, 33 TO 88
        statements
    CASE IS < 4, IS > 88, 5 TO 8
        statements
    CASE ELSE
        statements
END SELECT

Each SELECT CASE must have one and one only matching END SELECT statement. Any number of SELECT…CASE statements can be nested inside the CASE statements of other SELECT…CASE statements.