JavaScript_Succinctly

Chapter 10 Object()
Conceptual overview of using Object() objects
Using the built-in Object() constructor function, we can create generic empty objects
on the fly. In fact, if you remember back to the beginning of Chapter 1, this is exactly
what we did by creating the cody object. Let’s recreate the cody object.
Sample: sample69.html
var cody = new Object(); // Create an empty object with no properties.
for (key in cody) { // Confirm that cody is an empty generic object.
if (cody.hasOwnProperty(key)) {
console.log(key); // Should not see any logs, because cody itself
has no properties.
}
}
Here, all we are doing is using the Object() constructor function to create a generic
object called cody. You can think of the Object() constructor as a cookie cutter for
creating empty objects that have no predefined properties or methods (except, of
course, those inherited from the prototype chain).
Notes
If it’s not obvious, the Object() constructor is an object itself. That is, the constructor
function is based on an object created from the Function constructor. This can be
confusing. Just remember that like the Array constructor, the Object constructor
simply spits out blank objects. And yes, you can create all the empty objects you like.
However, creating an empty object like cody is very different than creating your own
constructor function with predefined properties. Make sure you understand that cody is
just an empty object based on the Object() constructor. To really harness the power of
JavaScript, you will need to learn not only how to create empty object containers from
Object(), but also how to build your own "class" of objects (e.g., Person()) like the
Object() constructor function itself.
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