ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Internationalizing applications
Sorting and comparing strings
Flash Player 10.1 and later, Adobe AIR 2.0 and later
Collation is the process of arranging things in their proper order. Collation rules vary significantly by locale. The rules
also differ if you are sorting a list or matching similar items, such as in a text search algorithm.
When sorting, small differences such as upper and lowercase letters or diacritic marks such as accents, are often
significant. For example, the letter ö (o with a diaeresis) is considered mostly equivalent to the plain letter o in French
or English. The same letter, however, follows the letter z in Swedish. Also, in French and some other languages, the last
accent difference in a word determines its order in a sorted list.
When searching, you often want to ignore differences in case or diacritics, to increase the chance of finding relevant
matches. For example, a search for the characters “cote” in a French document conceivably returns matches for “cote”,
“côte”, and “coté”.
Using the Collator class
The main methods of the Collator class are the compare() method, used primarily for sorting, and the equals() method,
used for matching values.
The following example shows the different behavior of the compare() and equals() methods.
var words:Array = new Array("coté", "côte");
var sorter:Collator = new Collator("fr-FR", CollatorMode.SORTING);
words.sort(sorter.compare);
trace(words); // côte,coté
var matcher:Collator = new Collator("fr-FR", CollatorMode.MATCHING);
if (matcher.equals(words[0], words[1]))
{
trace(words[0] + " = " + words[1]); // côte = coté
}
The example first creates a Collator object in SORTING mode for the French-France locale. Then it sorts two words
that differ only by diacritical marks. This shows that the SORTING comparison distinguishes between accented and
non-accented characters.
The sorting is performed by passing a reference to the Collator object’s sort() method as a parameter to the Array.sort()
method. This technique is one of the most efficient ways of using a Collator object to control sort order.
The example then creates a Collator object in MATCHING mode. When that Collator object compares the two words, it
treats them as equal. That shows that the MATCHING comparison values accented and non-accented characters the same.
Customizing the behavior of the Collator class
By default, the Collator class uses string comparison rules obtained from the operating system based on the locale and
the user’s system preferences. You can customize the behavior of the compare() and equals() methods by explicitly
setting various properties. The following table lists the properties and the effect they have upon comparisons:
Last updated 6/6/2012
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