Objects, Objects Everywhere
In actuality, everything in Flash Actionscript is an object. Not only are generic objects, movieclips and other obvious objects (such as the XML object), but also buttons, textfields, arrays, strings, numbers and even functions. Each one is considered an object in Actionscript in some way shape or form. This is an important bit of information to understand when working with Flash Actionscript. The fact that everything you define is an object will help you better work with your variables and use them the best way you can.

You already saw how movieclips are objects. Think of an array. We can take any array and also add our own custom values to it as well.

myArray = [];

myArray.home = "Alaska";

trace(myArray.home); // traces "Alaska"

 
Now there are some exceptions that kind of break the definition of what an object is – at least as you know it – though still technically qualify as an object. These are certain definitions of numbers, strings and boolean (true or false) values. You might have already figured this out or have known about these differences. Numbers, strings and true/false variables defined directly with their value are 1) variables not defined as an object reference and 2) not container object variables capable of holding values other than their own. For example, consider a variable defined to be 5. When using a direct assignment of that value to the number 5, it then is a variable not able to hold others.

myNumber = 5;

myNumber.home = "Atlantis";

trace(myNumber.home); // traces undefined as it does not exist

The same applies to strings defined directly with a quoted string and booleans set directly to true or false.

myString = "Hello";

myString.home = "Angkor";

trace(myString.home); // traces undefined as it does not exist

 

myBoolean = true;

myBoolean.home = "Barakus";

trace(myBoolean.home); // traces undefined as it does not exist

Also, if you assign two separate variables to have the same value, they will in fact be equivalent unlike with objects as they are references

num1 = 5;

num2 = 5;

trace(num1 == num2); // traces true

Assigning values in this manner for numbers, strings and booleans can be considered the shorthand method, much in the way curly braces ({}) are used for a shorthand method of generic objects. Only here, the shorthand method used for defining numbers, strings and booleans make them less object-like. These variable structures also have an long form (or object form) of definition, very similar to the definition of other objects, like so

myNumber = new Number(5);

myString = new String("Hello");

myBoolean = new Boolean(true);

For these variables now, each exist as variable objects capable of having other variable values contained within them. They still have their same base value, they’re just now capable of containing other values as well – as you would expect from objects.

myNumber = new Number(5);

myString = new String("Hello");

myBoolean = new Boolean(true);

 

myNumber.home = "Atlanta";

myString.home = "Anchorage";

myBoolean.home = "Baltimore";

 

trace(myNumber.home); // traces "Atlanta"

trace(myBoolean.home); // traces "Anchorage"

trace(myString.home); // traces "Baltimore"

This use of the long syntax in object definition is just like declaring generic object Objects with a base value. Any kind of variable you make in Flash (aside from functions) can be defined this way. The truth is, when you define an generic object in that manner, using a base value, it is actually converting the new Object call into a new Number or a new String call based on what you passed in for the base value. A generic object technically can’t have a base value and still be an object Object. That base value means it has to be some other object such as a number, string etc. which is representative of that type of value.

So what makes basic numbers, strings and booleans objects? Nothing about them seems to show that they are an object. How can they be objects? Well, simply speaking, an object in Flash is just the concept of understanding for Flash when it comes to a variable type. Objects have inherent in their being, more than just a base value. A simple number is actually more than a simple number. There’s other hidden functionality as every number is in its own way an object. This can be seen better in strings.

Think about a string and what you can do with it in ActionScript. Actionscript gives you all kinds of useful commands for controlling and manipulating strings. For example, you have the ability to convert a string to be all uppercase using the toUpperCase method.

title = "capitalize";

trace(title.toUpperCase()); // traces CAPITALIZE

Notice how the toUpperCase is used on the title variable using dot syntax as if it were included in the string as an object. In fact, in a way, it is! As a string, it inherently has access to all methods associated with strings – this even if the string was not declared in an object manner with new Object() or new String(). With this, you can see where a non object variable demonstrates object behavior.

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