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Operators in Javascript


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Javascript Operators

Operators are simply some functions having a arithmatic, logical or bitwise property. To start with, we will to through arithmetic operators first as we know maths.

Arithmatic Operators

OperatorProperty
+Addition
Substraction
*Multiplication
\Division
%Mod
=Assignment
++Increment
Decrement

 

We are quite familiar with some of the operators but we’ll learn each on in detail.

Addition

var num1 = 10;
var num2 = 20;
var total = num1+num2;		//total = 20

Here, total will hold the value of sum of the numbers.

Substraction

var num1 = 10;
var num2 = 20;
var total = num1-num2;		//total = -10

Here, total will hold the value of difference of the numbers, with sign, (-) in this case.

Multiplication

var num1 = 10;
var num2 = 20;
var total = num1*num2;		//total = 200

Here, total will hold the value of multiplication of the numbers.

Division

var num1 = 10;
var num2 = 20;
var total = num1/num2;		//total = 0.5

Here, total will hold the value of quotient. 0.5 in this case.

Modulus

var num1 = 10;
var num2 = 20;
var total = num1%num2;		//total = 10

Here, total will hold the value of remainder.10 in this case.

Assignment

var num1 = 10;
var num2;
var num2 = num1;		//num2 = num1 = 10

Here, num2 will hold the value of num1. The assignment is done from right to left hand side. Simple Maths, isn’t it.

Increment

var num = 10;
var total = num++;		//total = 11
var total = num+=4;		//total = 11+4 = 15

Increment operator is just like addition, but used when you need to add a numeric value to the variable itself.

READ  Javascript String to Array

Decrement

var num = 10;
var total = num--;		//total = 9
var total = num-=2;		//total = 9-2 = 7

Increment operator is just like substraction, but used when you need to substract a numeric value from the variable.

Note – You can also use increment/decrement with mulitiplication, division and modulus operators as well. Try this in the browser.

String Operators

Unlike arithmatic operators, + is the only operator which is used to concatinate 2 or more strings together.

var first = "Fname";
var last = "Lname";
var name = first + " " + last;		//Fname Lname

var first = "Fname";
var name +=" Lname";			//Fname Lname
var name = first + " Lname";		//Fname Lname

String and Numbers

In Javascript you can add numbers and strings together and the output will be a string.

var number = 10;
var name = 'Name';
var result = number+name;	//10name
result = name+number;		//name10

Comparision Operators

OperatorProperty
==Equal to
!=Not Equal to
===Equal to and equal type
!==Equal to not equal type
>Greater than
<Less than
>=Greater than equal to
<=Less than equal to

 

Logical Operators

OperatorProperty
&&Logical and
||Logical or
!Logical not

 

We will go through these operators in more details in the next section when we will cover conditional statements.

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