Hi
and welcome to this tutorial. This tutorial covers SharedObject.
SharedObject is a kind of cookie for Flash. Though, SharedObject is
much more powerful. SharedObject isn't just a way of saving mere
strings on the client's hard disk, you can store texts, strings,
numbers and even objects. For instance, if you want to save a date
object in JavaScript you would have to go though a whole encoding
process, with SharedObject you just save it, and be ready.
Starting with SharedObject
SharedObject is pretty simple to work with. First you need to call a
saved object. This is done with the getLocal() function. getLocal is
part of the SharedObject class and expects one parameter: the name of
the object you want to call. If the object doesn't exist, it is
created; now isn't that nifty. Anyway, the value that is returned by
SharedObject.getLocal() is your cookie. It holds all the saved data and
the functions you need to contol it. It's really easy to define
variables in the sharedObject. All the data is held in the data object.
So to define a variable all you have to do is define a variable in the
data object. A little example:
myOjbect = SharedObject.getLocal("test"); //Get the 'test' SharedObject and save it in myObject
myObject.data.myName = "Mark"; //Save the value "Mark" in the myName variable in the SharedObject
Now that the variables are created, there is one more thing you need
to know. When you edit the object, the SharedObject isn't saved. If
Flash would do that, it would be very inefficient, and would take up a
lot of system resources. That's why Flash only saves the SharedObject
when you tell it to. You can do that with the flush() function. When
you call this function, all the values are saved:
myOjbect = SharedObject.getLocal("test"); //Get the 'test' SharedObject and save it in myObject
myObject.data.myName = "Mark"; //Save the value "Mark" in the myName variable in the SharedObject
myObject.flush(); //Save the values
Now all the values are saved. Calling works in exactly the same way.
 First run |
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 Second run |
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Last little tips
You've now basicly grasped sharedObject. All that remains are a few
little leads. First is that you can check if you've allready defined a
variable or not by comparing it to undefined:
if (myOjbect.data.myName == undefined) {
//Variable doesn't exist so define it...
myObject.data.myName = "Mark";
} else {
//Do stuff with the existing variable...
trace(myObject.data.myName);
}
Or saving objects to the sharedObject...:
myObject.data.myArray = new Array();
myObject.data.myObject = new Object();
myObject.data.myObject.myFunction = function () {
trace("function called!");
}
The possibilities are endless :)
