ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with arrays
Note that the key named aspect ratio contains a space character. This is possible with the array access ([]) operator,
but generates an error if attempted with the dot operator. Using spaces in your key names is not recommended.
The second way to create an associative array is to use the Array constructor (or the constructor of any dynamic class)
and then use either the array access ([]) operator or the dot operator (.) to add key and value pairs to the array. If you
declare your associative array to be of type Array, you cannot use an object literal to initialize the array. The following
example creates an associative array named monitorInfo using the Array constructor and adds a key called type and
a key called resolution, along with their values:
var monitorInfo:Array = new Array();
monitorInfo["type"] = "Flat Panel";
monitorInfo["resolution"] = "1600 x 1200";
trace(monitorInfo["type"], monitorInfo["resolution"]);
// output: Flat Panel 1600 x 1200
There is no advantage in using the Array constructor to create an associative array. You cannot use the Array.length
property or any of the methods of the Array class with associative arrays, even if you use the Array constructor or the
Array data type. The use of the Array constructor is best left for the creation of indexed arrays.
Associative arrays with object keys (Dictionaries)
Flash Player 9 and later, Adobe AIR 1.0 and later
You can use the Dictionary class to create an associative array that uses objects for keys rather than strings. Such arrays
are sometimes called dictionaries, hashes, or maps. For example, consider an application that determines the location
of a Sprite object based on its association with a specific container. You can use a Dictionary object to map each Sprite
object to a container.
The following code creates three instances of the Sprite class that serve as keys for the Dictionary object. Each key is
assigned a value of either GroupA or GroupB. The values can be of any data type, but in this example both GroupA and
GroupB are instances of the Object class. Subsequently, you can access the value associated with each key with the array
access ([]) operator, as shown in the following code:
Last updated 6/6/2012
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