ACTIONSCRIPT 3.0

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with local SQL databases in AIR
You can choose to perform database operations asynchronously, meaning the database engine runs in the background
and notifies you when the operation succeeds or fails by dispatching an event. You can also perform these operations
synchronously. In that case the database operations are performed one after another and the entire application
(including updates to the screen) waits for the operations to complete before executing other code. For more
information on working in asynchronous or synchronous execution mode, see “Using synchronous and asynchronous
database operations” on page 753.
Connecting to a database
Adobe AIR 1.0 and later
Before you can perform any database operations, first open a connection to the database file. A SQLConnection
instance is used to represent a connection to one or more databases. The first database that is connected using a
SQLConnection instance is known as the “main” database. This database is connected using the open() method (for
synchronous execution mode) or the openAsync() method (for asynchronous execution mode).
If you open a database using the asynchronous openAsync() operation, register for the SQLConnection instance’s
open event in order to know when the openAsync() operation completes. Register for the SQLConnection instance’s
error event to determine if the operation fails.
The following example shows how to open an existing database file for asynchronous execution. The database file is
named “DBSample.db” and is located in the user’s “Pointing to the application storage directory” on page 672.
import flash.data.SQLConnection;
import flash.data.SQLMode;
import flash.events.SQLErrorEvent;
import flash.events.SQLEvent;
import flash.filesystem.File;
var conn:SQLConnection = new SQLConnection();
conn.addEventListener(SQLEvent.OPEN, openHandler);
conn.addEventListener(SQLErrorEvent.ERROR, errorHandler);
// The database file is in the application storage directory
var folder:File = File.applicationStorageDirectory;
var dbFile:File = folder.resolvePath("DBSample.db");
conn.openAsync(dbFile, SQLMode.UPDATE);
function openHandler(event:SQLEvent):void
{
trace("the database opened successfully");
}
function errorHandler(event:SQLErrorEvent):void
{
trace("Error message:", event.error.message);
trace("Details:", event.error.details);
}
Last updated 4/22/2013
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