CASE

The CASE statement allows the programmer to execute a particular sequence of instructions based upon the results of a series of test expressions.

COMMAND SYNTAX

        BEGIN CASE
        CASE expression statement(s)
        CASE expression
        *statement(s)
        *. . .
        END CASE

SYNTAX ELEMENTS

The BEGIN CASE and END CASE statements bound the CASE structure. Within this block, an arbitrary number of CASE expression statements may exist followed by any number of jBC statements. The expression should evaluate to a TRUE or FALSE result. The evaluation of each expression at execution time is in order. If the expression returns a TRUE result, it then executes the statements below. On completion of the associated statements, execution will resume at the first statement following the END CASE.

NOTES:

A default action (to trap error conditions for instance) may be introduced by using an expression that is always TRUE, such as "CASE 1". This should always be the last expression in the CASE block.

EXAMPLE

       V.STRING = 'B'
       GOSUB CHK.IT
       V.STRING = 'ABC'
       GOSUB CHK.IT
       STOP
    *
    CHK.IT:
    *
       BEGIN CASE
       CASE V.STRING EQ 'A'
          CRT 'an A'
       CASE  V.STRING EQ 'B'
          CRT 'a B'
       CASE V.STRING EQ 'C'
          CRT 'a C'
       CASE 1
          CRT 'neither A nor B nor C'
       END CASE
       RETURN
    END

Output:

     a B
     neither A nor B nor C