MACROMEDIA FLASH MX 2004-ACTIONSCRIPT LANGUAGE Reference page 338

this.radius = radius;
this.getArea = function(){
return Math.PI*this.radius*this.radius;
};
this.getDiameter = function() {
return 2*this.radius;
};
this.setRadius = function(param_radius) {
this.radius = param_radius;
}
}
// ActionScript 2.0 code that uses the Circle class
var myCircle:Circle = new Circle(5);
trace(myCircle.getArea());
trace(myCircle.getDiameter());
myCircle.setRadius("10");
trace(myCircle.radius);
trace(myCircle.getArea());
trace(myCircle.getDiameter());
See also
class, implements
338 Chapter 2: ActionScript Language Reference