Page 145 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

return this.firstName + “ “ + this.lastName;
};

var person1 = new Person(“Alice”, “Smith”);
4 Encapsulation:
• Encapsulation can be achieved through closures and private variables within functions.
function Counter() {
var count = 0;

this.increment = function() {
count++;
};
this.getCount = function() {

return count;
};
}
var counter = new Counter();
counter.increment();
console.log(counter.getCount()); // Outputs: 1
5 Polymorphism:
• JavaScript supports polymorphism through dynamic typing, allowing objects to be used in multiple contexts
without explicit type definitions.
function displayInfo(obj) {
console.log(obj.getDetails());
}
var student = {
name: “Bob”,
getDetails: function() {
return “Student: “ + this.name;
}
};

displayInfo(student); // Outputs: Student: Bob
In summary, JavaScript’s object-oriented development is centered around objects, prototypes, and constructor
functions. It offers a flexible and dynamic approach to building and extending objects, making it well-suited for
web development where dynamic and responsive behaviors are essential.

Document Object Model

The document object represents the whole html document.
When html document is loaded in the browser, it becomes a document object. It is the root element that represents
the html document. It has properties and methods. By the help of document object, we can add dynamic content
to our web page.
As mentioned earlier, it is the object of window. So
window.document

Is same as

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CITS : IT&ITES - Computer Software Application - Lesson 37 - 46