16.1. Storing and Retrieving Locally Persistent Information
You want to store information on a client’s computer that persists between movies and sessions.
Use a local shared object (LSO).
Local shared objects are to Flash what cookies are to web
browsers—but more so. They are called “super
cookies” by some developers because they allow you
to store potentially large amounts of data (if the user allows) and
because they also allow you to store and retrieve many native
ActionScript datatypes (as well as objects created from custom
classes). Local shared object files are saved to the client computer.
Flash movies within the same domain can write to and read from these
files by means of ActionScript’s
getLocal( ) method is the mechanism
by which LSOs are both created and opened for reading. The method
requires at least one parameter—a string that specifies the
name of the shared object to create or open:
my_l_so = SharedObject.getLocal("myFirstLSO");
getLocal( ) method attempts to first locate
an existing LSO by the specified name stored on the client computer.
If none is found, Flash creates a new LSO with that name. In either
case, the existing or new LSO is opened. The
) method returns a
instance. It is used instead of the
to instantiate a new local shared object.
For a complete example of how to create, write to, and save a local shared object, see Recipe 16.4.
Recipe 16.5 discusses ...