ActionScript for Flash MX: The Definitive Guide, Second Edition

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Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

Exiting and Returning Values from Functions

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trace("The name is " + first + " " + middle + " " + last);

}

Exiting and Returning Values

from Functions

Unless instructed otherwise, a function will end naturally when the interpreter fin-

ishes executing the last statement in the function’s body. You can, however, termi-

nate a function before the last statement is reached. Additionally, a function can

return a result (send back a value) to the code that invoked it. Let’s see how these

things work.

Terminating a Function

The return statement, which we introduced in Chapter 6, can be used to terminate a

function and, optionally, to return a result. When the interpreter encounters a return

statement during a function execution, it skips any remaining statements in the func-

tion. Consider this example:

function say (msg) {

return;

trace(msg); // This line is never reached

}

This example is not realistic, because its return statement always causes the function

to end before the trace() statement is reached. Therefore, the return statement is nor-

mally the last statement in a function body, unless it is used inside a conditional

statement. In the following example, we use return to exit the function if the pass-

word is not correct:

var correctPass = "cactus";

function enterSite(pass) {

if (pass ...