.in loop.
You can add additional properties onto your object at any time by using dot or bracket
notation:
customObject.value = 6;
customObject["otherValue"] = 7;
customObject.newMethod = function(){};
CHAPTER 3 n OBJECT-ORIENTED PROGRAMMING 63
The object literal is limited in that you can??™t use it as a class to instantiate new objects.
One object is defined, and that??™s it. Having only one of an object can be a very good thing.
Sometimes you want only a central location to manage things (this is often referred to as a
singleton design pattern).
nNote Design patterns are recurring approaches to a problem. By understanding the various approaches
to solving a problem, you can choose the solution that best fits a problem you might be having. Read more
about design patterns in Wikipedia at http://en.wikipedia.org/wiki/Design_pattern_
(computer_science).
The ElementReady object defined in the last chapter is a great example. Here??™s a snippet of
that object:
var ElementReady={
polled:[], /* store polled elements */
timer:null, /* store timer */
timerStarted: false,
ceasePoll:function()
{
clearTimeout(this.timer);
this.timerStarted = false;
},
startPoll:function()
{
if(!this.timerStarted) this.timer = ~CCC
setTimeout(function(){ElementReady.check(false)},100);
}
}
The object literal made sense as a central point of access to control the execution of all
functions with just one timer.
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