ActionScript for Flash MX: The Definitive Guide, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

General Array-Manipulation Tools

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Of course, the comparison does not always have to involve simple strings and num-

bers. Here we sort an array of movie clips in ascending order, according to their pixel

area:

var clips = [square1, square2, square3];

function sortByClipArea (clip1, clip2) {

clip1area = clip1._width * clip1._height;

clip2area = clip2._width * clip2._height

return clip1area - clip2area;

}

clips.sort(sortByClipArea);

That’s a mighty fine sortin’ machine!

Flash MX adds another useful sorting method not available in Flash 5. When the ele-

ments of an array are objects that share a specific property name, we can use sortOn()

to sort the objects quickly according to that property. For details, see Array.sortOn()

in the Language Reference.

The slice() Method

Something of a subset of splice(), the slice() method retrieves a series of elements

from an array. Unlike splice(), slice() only retrieves elements. It creates a new array

and does not affect the array on which it is invoked. The slice() method has the fol-

lowing syntax:

origArray.slice(startIndex, endIndex)

where startIndex specifies the first element to retrieve and endIndex specifies the ele-

ment after the last element we want to retrieve. The slice() method returns a new

array containing a copy of the series of elements ...