Operators In Javascript.

Types in JavaScript Operators

*JS Arithmetic Operator
*JS Assignement Operator
*JS Relational Operator
*JS Conditional Operator
*JS Comparitional Operator
*JS Logical Operator

Operators are for Mathematical and Logical Computations

The Assignment Operator = assigns values

The Addition Operator + adds values

The Multiplication Operator * multiplies values

The Comparison Operator > compares values

Arithmetic operators perform arithmetic on numbers (literals or variables).

JavaScript Addition
JavaScript Addition

The Addition Operator (+) adds numbers:
Adding

let x = 5;
let y = 2;
let z = x + y;

Subtracting

The subtraction operator (-) subtracts numbers.
Example

let x = 5;
let y = 2;
let z = x - y;

JavaScript Multiplication

The Multiplication Operator () multiplies numbers:
**Multiplying*

let x = 5;
let y = 2;
let z = x * y;

Dividing

The division operator (/) divides numbers.
Example

let x = 5;
let y = 2;
let z = x / y;

JavaScript Assignment Operators
Assignment operators assign values to JavaScript variables.

Given that x = 10 and y = 5, the table below explains the assignment operators:

Logical Assignment Operators

The = Operator

The Simple Assignment Operator assigns a simple value to a variable.
Simple Assignment Examples

let x = 10;
let x = 10 + y;

The += Operator

The Addition Assignment Operator adds a value to a variable.
Addition Assignment Examples

let x = 10;
x += 5;

The -= Operator

The Subtraction Assignment Operator subtracts a value from a variable.
Subtraction Assignment Example

let x = 10;
x -= 5;

The *= Operator

The Multiplication Assignment Operator multiplies a variable.
Multiplication Assignment Example

let x = 10;
x *= 5; 

The **= Operator

The Exponentiation Assignment Operator raises a variable to the power of the operand.
Exponentiation Assignment Example

let x = 10;
x **= 5; 

The %= Operator

The Remainder Assignment Operator assigns a remainder to a variable.
Remainder Assignment Example

let x = 10;
x %= 5;

JavaScript Comparison

Comparison Operators

Comparison operators are used to compare two values.

Comparison operators always return true or false.

Given that x = 5, the table below explains the comparison operators:

JavaScript String Comparison

All the comparison operators above can also be used on strings:
Example

let text1 = "A";
let text2 = "B";
let result = text1 < text2;

Comparing Different Types

Comparing data of different types may give unexpected results.

When comparing a string with a number, JavaScript will convert the string to a number when doing the comparison. An empty string converts to 0. A non-numeric string converts to NaN which is always false.

Example

age = Number(age);
if (isNaN(age)) {
  voteable = "Input is not a number";
} else {
  voteable = (age < 18) ? "Too young" : "Old enough";
}

JavaScript Conditionals

Conditional Statements

Conditional Statements allow us to perform different actions for different conditions.

Conditional statements run different code depending on true or false conditions.

Conditional statements include:

if
if...else
if...else if...else
switch
ternary (? :)

When to use Conditionals

*Use if to specify a code block to be executed, if a specified condition is true
*Use else to specify a code block to be executed, if the same condition is false
*Use else if to specify a new condition to test, if the first condition is false
*Use switch to specify many alternative code blocks to be executed
*Use (? :) (ternary) as a shorthand for if...else

The if Statement

Use if to specify a code block to be executed, if a specified condition is true.

Syntax
if (condition) {
  // code to execute if the condition is true
}