ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with byte arrays
compressed size 4 bytes
uncompressed size 4 bytes
file name length 2 bytes
extra field length 2 bytes
file name variable
extra field variable
Following the file header is the actual file data, which can be either compressed or uncompressed, depending on the
compression method flag. The flag is 0 (zero) if the file data is uncompressed, 8 if the data is compressed using the
DEFLATE algorithm, or another value for other compression algorithms.
The user interface for this example consists of a label and a text area (taFiles). The application writes the following
information to the text area for each file it encounters in the .zip file: the file name, the compressed size, and the
uncompressed size. The following MXML document defines the user interface for the Flex version of the application:
The beginning of the program performs the following tasks:
Imports the required classes
import flash.filesystem.*;
import flash.utils.ByteArray;
import flash.events.Event;
Defines the user interface for Flash
import fl.controls.*;
//requires TextArea and Label components in the Library
var taFiles = new TextArea();
var output = new Label();
taFiles.setSize(320, 150);
taFiles.move(10, 30);
output.move(10, 10);
output.width = 150;
output.text = "Contents of HelloAir.zip";
addChild(taFiles);
addChild(output);
Defines the bytes ByteArray
var bytes:ByteArray = new ByteArray();
Last updated 6/6/2012
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