This command starts an IF control structure. The system evaluates the logical expression <condition>, and processes different statement blocks depending on the result. A statement block ends with either ELSEIF, ELSE, or ENDIF. You can nest IF control structures.

ELSEIF and ELSE are optional.

The last statement block is always terminated by ENDIF.

If the IF condition is true, eCATT executes all the statements up to the end of the following statement block and then continues processing after the ENDIF statement.

If the IF condition is not true, the following statement block is ignored. In this case, the following ELSEIF condition is evaluated. ELSEIF is executed in the same manner as IF.

ELSE begins a statement block which is processed if none of the IF or ELSEIF conditions are true.

To formulate conditions, you can use logical expressions containing the following operators:

Simple conditions have the form:

You can combine several logical expressions into a single logical expression. If the single logical expression is true:

• Only if all of the component expressions are true, link the expressions with AND.
• If at least one of the component expressions is true, link the expressions with OR.

To negate the result of a logical expression, you can precede it with the NOT operator.

NOT takes priority over AND. AND takes priority over OR. However, you can use parentheses to specify the processing sequence.