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.

Working with Strings

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The only difference is that since lastIndexOf() searches a string backward, start_index

refers to the rightmost character we want included in our search (not the leftmost). If

start_index is omitted, it defaults to string.length – 1 (the last character in the

string).

For example:

paradox = "pain is pleasure, pleasure is pain";

paradox.lastIndexOf("pain"); // Returns 30; indexOf( ) would return 0

The following returns 0 (the index of the first occurrence of the word “pain”),

because we started the backward search before the second occurrence of “pain”:

paradox.lastIndexOf("pain",29); // Returns 0

No regular expressions

Note that regular expressions (a powerful tool used to recognize patterns in textual

data) are not supported in ActionScript by default. However, developer Pavils Jur-

jans has made a custom RegExp object available at http://www.jurjans.lv/flash/

RegExp.html.

Retrieving Portions of Strings

Sometimes a long string contains a sequence of characters that we’d like to access

more conveniently. In the string “Steven Sid Mumby”, for example, we may want to

extract the last name, “Mumby”. To extract a shorter string (or substring), we use

one of these functions: substring(), substr(), splice(),orsplit(). We’ll cover how each

of them work before discussing performance ...