ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with arrays
Multidimensional arrays
Flash Player 9 and later, Adobe AIR 1.0 and later
Multidimensional arrays contain other arrays as elements. For example, consider a list of tasks that is stored as an
indexed array of strings:
var tasks:Array = ["wash dishes", "take out trash"];
If you want to store a separate list of tasks for each day of the week, you can create a multidimensional array with one
element for each day of the week. Each element contains an indexed array, similar to the tasks array, that stores the
list of tasks. You can use any combination of indexed or associative arrays in multidimensional arrays. The examples
in the following sections use either two indexed arrays or an associative array of indexed arrays. You might want to try
the other combinations as exercises.
Two indexed arrays
Flash Player 9 and later, Adobe AIR 1.0 and later
When you use two indexed arrays, you can visualize the result as a table or spreadsheet. The elements of the first array
represent the rows of the table, while the elements of the second array represent the columns.
For example, the following multidimensional array uses two indexed arrays to track task lists for each day of the week.
The first array, masterTaskList, is created using the Array class constructor. Each element of the array represents a
day of the week, with index 0 representing Monday, and index 6 representing Sunday. These elements can be thought
of as the rows in the table. You can create each day’s task list by assigning an array literal to each of the seven elements
that you create in the masterTaskList array. The array literals represent the columns in the table.
var masterTaskList:Array = new Array();
masterTaskList[0] = ["wash dishes", "take out trash"];
masterTaskList[1] = ["wash dishes", "pay bills"];
masterTaskList[2] = ["wash dishes", "dentist", "wash dog"];
masterTaskList[3] = ["wash dishes"];
masterTaskList[4] = ["wash dishes", "clean house"];
masterTaskList[5] = ["wash dishes", "wash car", "pay rent"];
masterTaskList[6] = ["mow lawn", "fix chair"];
You can access individual items on any of the task lists using the array access ([]) operator. The first set of brackets
represents the day of the week, and the second set of brackets represents the task list for that day. For example, to
retrieve the second task from Wednesday’s list, first use index 2 for Wednesday, and then use index 1 for the second
task in the list.
trace(masterTaskList[2][1]); // output: dentist
To retrieve the first task from Sunday’s list, use index 6 for Sunday and index 0 for the first task on the list.
trace(masterTaskList[6][0]); // output: mow lawn
Last updated 6/6/2012
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