JavaScript Objects

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, dataObj.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 . 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().


A new instance of an object:

dataObj=new Object();

dataObj.firstname="Jonti";
dataObj.lastname="Leff";
dataObj.age=40;
dataObj.eyecolor="red";


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