1. >> Introduction to JavaScript

2. Web-Based Systems - Misbhauddin
Pop-up Boxes in JS
ALERT
alert("Welcome to the Class");
CONFIRM
confirm("Are you sure you want to take IS-311?");
PROMPT
prompt("What is XML?", ":(");
Returns a value also
Web-Based Systems - Misbhauddin

3. Functions in JavaScript
SYNTAX
keyword
Mainly used for event-handling in Web Development
Can also be called from other functions (Reuse)
function name() { }
TRY NOW
function test() {
alert(“Tested”); }
Tip: Make it work by calling the function
Web-Based Systems - Misbhauddin

4. Functions in JavaScript
function name(parameters) {
return b; }
You can use as many parameters as you like
Can also return values (numbers, strings, boolean)
Use return statement
function test(x) {
alert(x); }
TRY NOW
Web-Based Systems - Misbhauddin

5. Objects - Introduction
JavaScript is Object-Oriented
Properties
 They have a value
Object
Methods
'things that do
something
Example
var abc = “Hello World”;
abc.length;
document.write(“Hello World”);
method
property
Web-Based Systems - Misbhauddin

6. Web-Based Systems - Misbhauddin
Objects - Definition
Objects
Objects allow us to represent in code real world things and entities
Such as a person or bank account
SYNTAX
TRY NOW
keyword
var object-name = {
………. }
Create an object called “student”
Web-Based Systems - Misbhauddin

7. Web-Based Systems - Misbhauddin
Properties in Objects
Properties
Each piece of information we include in an object is known as a property. 
Each property has a name, followed by : and then the value of that property
SYNTAX
TRY NOW
keyword
var object-name = {
property-name: value, }
Add two attributes with your name and major
Note: Separate each property using a comma (,) and not a semicolon as in Java
Web-Based Systems - Misbhauddin

8. Using Properties from Objects
Use the “.” dot notation
Remember the length property you used with strings
SYNTAX
TRY NOW
ObjectName.PropertyName;
Display the properties from the student object using document.write() function
Web-Based Systems - Misbhauddin

9. Using Properties from Objects
Use the brackets notation []
Remember the length property you used with strings
SYNTAX
TRY NOW
ObjectName["PropertyName"]
Repeat using brackets now.
Display the properties from the student object using document.write() function
Note: We need " " around the property's name.
Web-Based Systems - Misbhauddin

10. Objects using Constructor
Uses the “new” keyword
Remember the length property you used with strings
Adding Properties using constructor method
SYNTAX
keyword
var ObjectName = new Object();
ObjectName.PropertyName=value;
Web-Based Systems - Misbhauddin

11. Web-Based Systems - Misbhauddin
Try Now
Create an object called BMW, which should have 3 properties: a cost of “too much",  speed of 220 and country of "Germany"
Using Constructor Method
Using Object Literal Notation
var BMW={
cost:"too much“,
speed:220,
country:"Germany“ }
var BMW=new Object();
BMW.cost="too much";
BMW.speed=220;
BMW.country="Germany";
Web-Based Systems - Misbhauddin

12. Web-Based Systems - Misbhauddin
Methods in Objects
Methods
A method is just like a function associated with an object
Each property has a name, followed by : and then the value of that property
SYNTAX
objectName.functionName = function (parameter) {
…………………….. };
TRY NOW
Create a method to change the major and set it to the attribute value
Web-Based Systems - Misbhauddin

13. Methods in Objects – “this” keyword
We can make a method work for many objects using “this” keyword
 Refer to whichever object called that method 
Note: should associate with object
Using the object-name
Using “this” keyword
student.changeMajor=function(x) {
student.major=x; }
var changeMajor=function(x){
this.major=x; }
student.changeMajor=changeMajor;
Web-Based Systems - Misbhauddin

14. Next on JavaScript Arrays Object Models Forms
Using the Document Object Model (DOM)
Using the Browser Object Model (BOM)
Forms
Validation