Beginning Web Development, Silverlight, and ASP.NET AJAX

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CHAPTER 14 ■ JAVASCRIPT PROGRAMMING WITH ASP.NET AJAX
car, such as its color, a method is something that you can perform on the car, such as
driving it, and an event is something the car informs you of and that you can respond to,
such as the little red light that comes on when you are nearly out of gas.
In ASP.NET AJAX, properties are either set using dot notation or accessors. The rule
of thumb is that you can use dot syntax when the property is a primitive type (such as a
string), as follows:
MyCar.Color="Black";
Accordingly, you use the accessor syntax when the property is a complex object. The
accessor syntax uses get_ and set_ methods to get and set the value of the property. For
example, if your color settings are an object, then you will use the following:
MyCar.set_Color(ColorObject);
Methods are functions that you can call on an object, and that don’t necessarily need
a return parameter. For example, if you want to start the ignition on your car, you would
do it using a method like this:
MyCar.startEngine();
Events are actions that take place on your object that raise a notification. In Java-
Script, you specify the handler for the event by appending add to the event, specifying the
handler name. For example, if you want to handle an event for the fuel running low in
your car, you would write code like this:
MyCar.fuelLow.add(FuelLowHandler);
And you would then implement the specified function like this:
Function FuelLowHander(sender,args)
{
...
}
Using Namespaces in JavaScript
Namespaces are a methodology that you can use to group similar classes together to
make for easier management. For example, if you are building a library of classes for
common objects, such as car, boat, house, person, fruit, and dog, then it is a good idea to
group these into different namespaces, for manageability and extensibility. For example,
you could have a Vehicles namespace that car and boat live in. Then, if you were to create
an airplane class, it would live in the same namespace. Also, consider the scenario where