Decision Structures

Decision structures allow you to execute one or more lines of code based upon conditions tested, and then perform different operations depending on the results of that test. You can test for a condition being true or false, for specific values of an expression, or for various exceptions generated when you execute statements. The decision structures supported by Encore RPG include:

  • IF…THEN…ELSE process a group of commands when a comparison expression evaluation is True(IF), or False(ELSE). The comparison expression is evaluated at the end of the commands, and if the expression is true, the group of commands are executed again. An ENDIF or END command is required to end the group of commands.
  • SELECT conditionally processes one of several alternative sequences of operations. It consists of a SELECT statement, zero or more WHEN groups, an optional OTHER group, and terminates with an END or ENDSL statement. You can also use CASE, to specify a comparison expression to select a subroutine for processing when the condition evaluates *True.
  • TRY..CATCH..FINALLY provides a way to trap possible errors that may occur in code segments, while still running the code. The TRY statements are executed first, any exceptions are trapped with the CATCH commands, and FINALLY commands are executed when no exceptions are trapped. An ENDTRY command is required to end the group of commands.

Loop Structures

Discusses control-flow commands used to repeat processes.

Nested Control Structures

Explains control-flow commands inside other control-flow commands.

See Also

CASEDFT

TRY

CATCH

FINALLY

Encore RPG Language Reference