User Guide

30 Chapter 2: Director Scripting Essentials
When writing if...then structures in Lingo, you can place the statement or statements
following
then in the same line as then, or you can place them on their own line by inserting a
carriage return after
then. If you insert a carriage return, you must also include an end if
statement at the end of the if...then structure.
When writing
if structures in JavaScript syntax, you can place the statement or statements
following
if in the same line as if, or you can place them on their own line by inserting a
carriage return after
if.
For example, the following statements are equivalent:
-- Lingo syntax
if _mouse.mouseMember = member(1) then _movie.go("Cairo")
if _mouse.mouseMember = member(1) then
_movie.go("Cairo")
end if
// JavaScript syntax
if (_mouse.mouseMember = member(1)) { _movie.go("Cairo"); }
if (_mouse.mouseMember = member(1)) {
_movie.go("Cairo");
}
For reference information on using the if...then...else and if...else structures, see “if”
on page 209.
Evaluating and matching expressions
The
case (Lingo) or switch...case (JavaScript syntax) structures are shorthand alternatives to
using
if...then...else or if...then structures when setting up multiple branching
structures. The
case and switch...case structures are often more efficient and easier to read
than many
if...then...else or if...then structures.
In Lingo, the condition to test for follows the term
case in the first line of the case structure.
The comparison goes through each line in order until Lingo encounters an expression that
matches the test condition. When a matching expression is found, Director executes the Lingo
that follows the matching expression.
In JavaScript syntax, the condition to test for follows the term
switch in the first line of the
structure. Each comparison in the test follows the term
case for each line that contains a test.
Each
case comparison can be ended by using the optional term break. Including the term break
breaks the program out of the
switch structure and executes any statements following the
structure. If break is omitted, the following case comparison is executed.
A
case or switch...case structure can use comparisons as the test condition.
For example, the following case and switch...case structures test which key the user pressed
most recently and responds accordingly.
• If the user pressed A, the movie goes to the frame labeled Apple.
• If the user pressed B or C, the movie performs the specified transition and then goes to the
frame labeled Oranges.