This document provides an overview of JavaScript concepts including: - Common JavaScript functions like alert(), write(), and typeof. - JavaScript data types like strings, numbers, Booleans, arrays, and objects. - How to declare variables, use comparison and arithmetic operators, write if/else statements. - How to create and access elements in arrays, including multidimensional arrays. Loops and math functions are also discussed. The document serves as an introductory guide to JavaScript syntax and fundamentals through examples and explanations of common programming concepts.

2. Topic
JavaScript
Group Member:
• Hamza Khan
• Mohammad Sajid
• Abdul Wahab

3. What can we do with Java Script
•Make webpage interactive
•Slider
•Image Galleries
•Form Validation
•Game Development

4. Java Script tag
• <script type=“text/Java script”></script>

5. How To Generate Message
Alert(“Hello world”);

6. Document.write Function in javascript
written on web page
• Document.write();
Show on web page
Document.write(“Hello world”);

7. Document.write Function in javascript
• Heading on webpage by javaScript
Document.write(“<h1>Hello</h1>”)

8. Types in java Script
1-String
2-Number
3-Boolean
4-Array
5-Object

9. Variable in java Script
• Variable are used to hold or store data
How to take data type in java script
Var name=“Ali Bhai”;
Alert(name);
Alert(typeof name);

10. Variable in java Script(cont)
Var num=25;
Alert(num);
Alert(typeof num);
Var Hk=“null”;
Alert(Hk);
(typeof object);

11. If-else Statement in javaScript
Syntax:
If(Condition){
//execute if block
}
Else{
//execute else block
}

12. If-else Statement in javaScript(con)
Var a=10;
Var b=11;
If(a==b)
{
Alert(“values are equal”);
}
Else
{
Alert(“Values are not equal”);
}

13. Functions in javascript
• Function eliminates the need of writing the
same code again and again.
Function welcome(){
Alert(“welcome to College”);
}
Welcome();
Welcome();

14. Airthmetic operations in JavaScript
• Addition +
• Subtraction –
• Multiplication *
• Division /
• (Division Reminder)%
• Increment ++
• Decrement --

15. Addition program in javaScript
Var add = 10 + 15;
document.write(add);
Here,
Operand=10 and 15
Operator= + sign

16. Subtraction program in javaScript
Var sub = 10 - 5;
document.write(sub);
Here,
Operand=10 and 15
Operator= - sign

17. Multiplication program in
javaScript
Var mul = 5 * 5;
document.write(mul);
Here,
Operand=5 and 5
Operator= * sign

18. Division program in javaScript
Var div = 5/5;
document.write(div);
Here,
Operand=5 and 5
Operator= / sign

19. Remainder program in javaScript
Var rem = 5%5;
document.write(rem);
Here,
Operand=5 and 5
Operator= % sign

20. Operator order of Precedence in javaScript
Var rem = 5+5*10;
document.write(rem);
First precedence Multiplication and
Division
Answer=55

21. Operator order of Precedence in
javaScript(Cont)
Var rem = (5+5)*10;
document.write(rem);
First Highest precedence is bracket
then Multiplication and Division
Answer=100

22. Increment and decrement operator in
javascript
Var Ans=10;
Ans++;
document.write(Ans);
Var Ans=11;
Ans--;
document.write(Ans);

23. Comparison operator in javascript
• ==(equal to)
• ===(equal value and type)
• !=(not equal)
• > greater than
• < Less than
• >= (greater than or equal to)
• < =(Less than or equal to)

24. Comparison operator in javascript(cont)
Var a=10, b=10
If(a==b){
document.write(“both values are
same”);
}
Ans=both values are same

25. Comparison operator in javascript(cont)
Var a=10, b=“10”
If(a===b){
document.write(“both values are same”);
}
Else{
document.write(“both values not are
same”);
}
Ans=not same
// because triple equal check values and
data type also

26. Comparison operator in javascript(cont)
Var a=10, b=5
If(a!=b){
document.write(“both values are not equal”);
}

27. Comparison operator in javascript(cont)
Var a=10, b=5
If(a>b){
document.write(“a greater than b”);
}

28. Comparison operator in javascript(cont)
Var a=10, b=5
If(a<b){
document.write(“a Less than b”);
}

29. Comparison operator in javascript(cont)
Var age=18
If(age >=18)
{
document.write(“you are eligible”);
}
Else{
Alert(“not Eligible”);
}
Ans=eligible

30. Math funcitons in javaScript
• Math.round();
• Math.sqrt();
• Math.power();
• Math.min();
• Math.max();
• Math.random();
• Math.floor(math.random() * 1000);

31. Loop in JavaScript
• For Loop
• While Loop
• Do while Loop

32. For loop in JavaScript
Syntax;
for(initialization; condition; increment/decriment )
E.g:
For(var i=1; i<6; i++)
{ document.write( “hello” + I + “ <br/ >” )
}

33. While Loop in javaScript
E.g:
var i=1;
While( i < 6 )
{ document.write( “hello”+ I + “ <br/ >” )
i++;
}

34. Do While loop in javaScript
E.g:
Var i=1;
do
{ document.write{“hello”+i+”<br>”}
i++;
}
While(i<6);

35. Array
Arrays
Data structures of related items
Each element has a position number
Dynamic
Size of an array in JavaScript can be changed
(increased) AFTER it is created

36. Arrays in JavaScript
• Each element referenced by a number
Start at “zeroth element”: 10 element array
has elements: 0,1,2 ,..,8,9
Subscript or index
• Accessing a specific element
Name of array
Brackets
Number of element
• Arrays know their length
length property

37. c[ 6 ]
-45
6
0
72
1543
-89
0
62
-3
1
6453
78
Name of array c[ 0 ]
c[ 1 ]
c[ 2 ]
c[ 3 ]
c[ 11 ]
c[ 10 ]
c[ 9 ]
c[ 8 ]
c[ 7 ]
c[ 5 ]
c[ 4 ]
Position number (index
or subscript) of the
element within array c
Fig. 11.1 A 12-element array.

38. Declaring and Allocating Arrays
• Arrays in memory
– Objects
– Operator new
• Allocates memory for objects
• Dynamic memory allocation operator
var c;  array declaration
c = new Array( 12 );  memory allocation

39. Using Arrays
• Arrays can grow dynamically
– Allocate more space as more items are added
than originally planned for
• Array elements must be initialized explicitly
– Default value is “undefined”
– for loops convenient fro initialization
– Referring to uninitialized elements or elements
outside array bounds is an error

40. Examples Using Arrays
• for…in statement
– Perform an action for each element in an array
– Iterates over array elements
• Assigns each element to specified variable one at a
time
– Ignores non-existent elements

41. Multidimensional Arrays
• Two-dimensional arrays analogous to tables
– Rows and columns
• Specify row first, then column
– Two subscripts

42. Multidimensional Arrays
a[ 1 ][ 0 ] a[ 1 ][ 1 ] a[ 1 ][ 2 ] a[ 1 ][ 3 ]
Row 0
Row 1
Row 2
Column 0 Column 1 Column 2 Column 3
Row subscript (or index)
Array name
Column subscript (or index)
a[ 0 ][ 0 ] a[ 0 ][ 1 ] a[ 0 ][ 2 ] a[ 0 ][ 3 ]
a[ 2 ][ 0 ] a[ 2 ][ 1 ] a[ 2 ][ 2 ] a[ 2 ][ 3 ]
Two-dimensional array with three rows and four columns.