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Time for action—determining the value of our options
The following steps help us to determine the value of our options:
- Right below where we use the
.bark()method onmyDog, type in the following code:document.write( 'My dog\'s name is ' + myDog.options.name + '.<br />'); document.write( 'My dog is a ' + myDog.options.type + '.<br />'); document.write( 'My dog is ' + myDog.options.age + ' years old.<br />');
- Open up your HTML document on the web browser, and after you exit out of the dialog box that
.bark()calls, you should see something like this:
Extending classes
Oftentimes, you'll want to extend a class with another class. For example, we might want to extend our Dog class with a class for show dogs that may use the same options, but may do other special things.
We can extend classes with the Extends property. Extends is a property specifically for classes, that not only inherits properties and methods from a parent class, it makes all parent methods available inside a method.