Objects are
created by using the new operator followed by the name of the object type to create. Developers
create their own objects by creating instances of the Object type and adding properties and/or
methods to it, as shown here:
var o = new Object();
Each Object instance has the following properties and methods:
constructor — The function that was used to create the object. In the previous example,
the constructor is the Object() function.
hasOwnProperty(propertyName) — Indicates if the given property exists on the object
instance (not on the prototype). The property name must be specifi ed as a string (for
example, o.hasOwnProperty(“name”)).
isPrototypeOf(object) — Determines if the object is a prototype of another object.
propertyIsEnumerable(propertyName) — Indicates if the given property can be
enumerated using the for-in statement (discussed later in this chapter). As with
hasOwnProperty(), the property name must be a string.
toLocaleString() — Returns a string representation of the object that is appropriate for
the locale of execution environment.
toString() — Returns a string representation of the object.
valueOf() — Returns a string, number, or Boolean equivalent of the object. It often
returns the same value as toString().
