Conditions Example: Using the Procedure.If Element

Tasks within Process Definitions can make use of the Procedure.If element to provide conditional processing. This element functions like a typical IF-THEN statement in procedural programming:

In the process definition example above, the "taskExport" task includes a Procedure.If element which has a conditional Expression attribute. If this expression evaluates to True, then all of the Procedure.If element's child elements will execute. If the expression is False, then processing will continue with the next element following the Procedure.If element's child elements. So, as shown above, if the "doExport" Request parameter equals 1, then the yellow-highlighted elements will execute; otherwise they'll be skipped.

Several other elements are available for use in controlling conditional branching:

Procedure.Else - This element must be a sibling of, and immediately follow, a Procedure.If element. It identifies a conditional block of procedures that will be run if the Procedure.If element immediately above it evaluates to False. If the Else block ran, the token @Procedure.myProcedureID.rdReturnValue~ returns True, otherwise it returns False.

Procedure.Switch - This element works with one or more child Procedure.Switch Case elements to define conditional blocks of procedures to be run when a specified value matches. Use it when there are multiple conditional blocks defined and just one of them is to be run, based on the value of a variable. You can also use a child Procedure.Switch Else element, which runs its block of procedures if none of the previous Switch Case elements match the specified value.

The value to test against is specified in the Expression attribute and can be literal value, a token, or even JavaScript that evaluates to a value. The Data Type attribute ensures comparisons, especially of dates, are made correctly.

Conditions give developers a useful tool, providing the ability to dynamically change their reports and allowing great flexibility when developing Logi applications.