Global Local variable and Math operators

Global and Local variable:

Global variable:

Any variable that is created outside the Function.

The global variable can be called inside or outside the function.

<script type=”text/javascript”>

var game = “Table Tennis”;

function firstPlay()

{

document.write (game);

}

firstPlay();

document.write(game);

Result:

Table Tennis Table Tennis

 

Local variable:

Any variable that is created inside the Function

The local variable can be called only inside the function.

<script type=”text/javascript”>

function firstPlay()

{

var game = “Table Tennis”;

document.write (game);

}

firstPlay();

document.write(game);

Result:

Table Tennis

Math Operators:

Below are the math operators in JavaScript:

Addition +

Subtraction -

Multiplication *

Division /

Modulus %

Increment ++

Decrement --

<script type=”text/javascript”>

var add = 25 + 4 ;

document.write(add);

</script>

Result: 29

<script type=”text/javascript”>

var subtract = 29 - 4 ;

document.write(subtract);

</script>

Result: 25

<script type=”text/javascript”>

var multiply = 25 * 4 ;

document.write(multiply);

</script>

Result: 100

<script type=”text/javascript”>

var divide = 12 / 4 ;

document.write(multiply);

</script>

Result: 3

<script type=”text/javascript”>

var divide = 15 / 4 ;

document.write(multiply);

</script>

Result: 3.75

<script type=”text/javascript”>

var modulus = 25 % 4 ;

document.write(modulus);

</script>

Result: 1

<script type=”text/javascript”>

var apple = 10 ;

apple++;

document.write(apple);

</script>

Result: 11

<script type=”text/javascript”>

var apple = 16 ;

apple--;

document.write(apple);

</script>

Result: 15

Functions

Calling a Function in new Function

In JavaScript, a user can call a Function from another Function such as:

<script type=”text/javascript”>

function firstCandy()

{

document.write (“ Hersheys”);

}

function secondCandy()

{

document.write (“ Toblerone”);

}

function goodCandy(){

firstCandy();

secondCandy();

}

goodCandy();

</script>

Output:

Hersheys Toblerone

Calling a Function within Function:

When we try calling the Functions within each other, it prints results like never ending cycle. It is bad programming.

<script type=”text/javascript”>

function firstCandy()

{

document.write (“ Hersheys”);

secondCandy();

}

function secondCandy()

{

document.write (“ Toblerone”);

firstCandy();

}

firstCandy();

</script>

Output:

Hersheys Toblerone Hersheys Toblerone Hersheys Toblerone Hersheys Toblerone

Hersheys Toblerone...