ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with the file system
The FileReference.load() method returns immediately after being called, but the data being loaded isn’t available
immediately. The FileReference object dispatches events to invoke listener methods at each step of the loading process.
The FileReference object dispatches the following events during the loading process.
open event (Event.OPEN): Dispatched when the load operation starts.
progress event (ProgressEvent.PROGRESS): Dispatched periodically as bytes of data are read from the file.
complete event (Event.COMPLETE): Dispatched when the load operation completes successfully.
ioError event (IOErrorEvent.IO_ERROR): Dispatched if the load process fails because an input/output error
occurs while opening or reading data from the file.
Once the FileReference object dispatches the complete event, the loaded data can be accessed as a ByteArray in the
FileReference object’s data property.
The following example shows how to prompt the user to select a file and then load the data from that file into memory:
package
{
import flash.display.Sprite;
import flash.events.*;
import flash.net.FileFilter;
import flash.net.FileReference;
import flash.net.URLRequest;
import flash.utils.ByteArray;
public class FileReferenceExample1 extends Sprite
{
private var fileRef:FileReference;
public function FileReferenceExample1()
{
fileRef = new FileReference();
fileRef.addEventListener(Event.SELECT, onFileSelected);
fileRef.addEventListener(Event.CANCEL, onCancel);
fileRef.addEventListener(IOErrorEvent.IO_ERROR, onIOError);
fileRef.addEventListener(SecurityErrorEvent.SECURITY_ERROR,
onSecurityError);
var textTypeFilter:FileFilter = new FileFilter("Text Files (*.txt, *.rtf)",
"*.txt;*.rtf");
fileRef.browse([textTypeFilter]);
}
public function onFileSelected(evt:Event):void
{
fileRef.addEventListener(ProgressEvent.PROGRESS, onProgress);
fileRef.addEventListener(Event.COMPLETE, onComplete);
fileRef.load();
}
public function onProgress(evt:ProgressEvent):void
{
trace("Loaded " + evt.bytesLoaded + " of " + evt.bytesTotal + " bytes.");
}
public function onComplete(evt:Event):void
Last updated 6/6/2012
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