Using the load() and save() methods

Flash Player 10 added the load() and save() methods to the FileReference class. These methods are also in AIR 1.5, and the File class inherits the methods from the FileReference class. These methods were designed to provide a secure means for users to load and save file data in Flash Player. However, AIR applications can also use these methods as an easy way to load and save files asynchronously.

For example, the following code saves a string to a text file:

var file:File = File.applicationStorageDirectory.resolvePath("test.txt");
var str:String = "Hello.";
file.addEventListener(Event.COMPLETE, fileSaved);
file.save(str);
function fileSaved(event:Event):void
{
    trace("Done.");
}

The data parameter of the save() method can take a String, XML, or ByteArray value. When the argument is a String or XML value, the method saves the file as a UTF-8–encoded text file.

When this code sample executes, the application displays a dialog box in which the user selects the saved file destination.

The following code loads a string from a UTF-8–encoded text file:

var file:File = File.applicationStorageDirectory.resolvePath("test.txt");
file.addEventListener(Event.COMPLETE, loaded);
file.load();
var str:String;
function loaded(event:Event):void
{
    var bytes:ByteArray = file.data;
    str = bytes.readUTFBytes(bytes.length);
    trace(str);
}

The FileStream class provides more functionality than that provided by the load() and save() methods:

• Using the FileStream class, you can read and write data both synchronously and asynchronously.

• Using the FileStream class lets you write incrementally to a file.

• Using the FileStream class lets you open a file for random access (both reading from and writing to any section of the file).

• The FileStream class lets you specify the type of file access you have to the file, by setting the fileMode parameter of the open() or openAsync() method.

• The FileStream class lets you save data to files without presenting the user with an Open or Save dialog box.

• You can directly use types other than byte arrays when reading data with the FileStream class.