Preface and Postscript Scripts

Use the Formula Editor to create and edit "formulas" in your forms in order to perform special calculations. Formulas may consist of simple calculations or complex sets of programming statements. When these are combined together they are called "scripts".

Preface Scripts

Preface scripts are executed at the very beginning when a form is first executed. This is a useful place at which to "initialise" variables and perform special operations before form or reporting printing begins. Preface scripts are optional. Any value you return from a Preface script is ignored.

Postscript Scripts

Postscript scripts are executed after a user has been prompted for form questions. Place script code that checks the validity of user responses to your questions here. You may also use a script to display warning messages about unacceptable responses to your questions.

If there are no form questions, the form is executed immediately after the preface script, unless you return a FALSE value. In that case the form's execution is cancelled.

If you have defined questions and a postscript script returns a FALSE value, the form questions list is redisplayed and the user must correct the entries they have made. It is recommended that you return a TRUE value if you find the user responses to your questions acceptable. Postscript scripts are optional.

End Report Scripts

If a file with the same name as your report, but ending with the extension .MAC is found in the same directory as your report, its contents is executed automatically by Visual Builder.

This is useful if you wish to perform a task after the report has been created (such as moving the data file it created or emailing it).

For example, if you have created a report called export.sty, and a file called export.mac exists in the same directory, its contents will be executed after export.sty has finished.

Creating Scripts

Functions

Press this button to view a list of functions available to use.

Operators

Press this button to view a list of available language operators available for use.

Statements

Press this button to view a list of available CAPITAL Business Script program commands/statements that may be used.

Test

Will test the calculation to see if it contains any errors that can be immediately detected.

Editor

Enter the calculation here. The calculation must consist of one or more valid lines of CAPITAL Business Script.

A sample preface script might simply consist of a series of variable declarations. For example:

Declare FirstDate Type Date

Declare LastDate Type Date

A postscript script might compare values and reject invalid user input. For example:

* It makes no sense if the end date is less

* than the start date

If LastDate < FirstDate

Echo The date range you have specified is invalid.

Return FALSE

Endif

Return TRUE

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