ActionScript: The Definitive Guide

Methods

Methods are functions that are associated with objects and are typically used to perform a task or access an object’s data. We invoke methods with the function call operator, ( ), using the dot operator to separate the method name from its object:

               objectName.methodName( )

For example:

ball.getArea( );  // Call the getArea( ) method of ball

As with properties, methods are defined for a class and then invoked on individual object instances. However, before we see how to create methods within a class, we’re going to bend the rules of good object-oriented programming and attach a method to an individual object instance of the built-in Object class. Once we understand how a single method works on an isolated object, we’ll apply the concept correctly to a class of our own.

A method is essentially just a function stored in an object property. By assigning a function to an object property, we turn that function into a method of the object:

// Create an object
myObject = new Object( );

// Create a function
function greet ( ) {
  trace("hello world");
}

// Now assign greet to the property sayHello
myObject.sayHello = greet;

Once a function resides in an object property, we may invoke that function as a method, like this:

myObject.sayHello( );  // Displays: "hello world"

Truth be known, you can also assign a function to an array element (instead of to an object property) and invoke that function using the call operator, like this:

var myList = new Array( ); myList[0] = greet; myList[0]( ); ...