Different between == and === in JavaScript examples
- Admin
- Dec 31, 2023
- Javascript
In this tutorial, We will have a look, at the difference between ==
and ===
in javascript with code examples.
This post covers examples and notes about the comparison of double equal signs
(==) and triple equal signs
(===) operators in JavaScript.
First, what do equal signs about?
Both operators are used to compare different values.
==
is called an equality operator
, which applies type coercion, what doe type coercion
, It converts the values before comparison.
m==n
returns true
if m and n are the same values
and types
, else false
.
===
is called identity operators
, which do not apply type coercion, not converting the values before conversion.
m===n
returns true
, if m and n are the same values
for strings
and the same reference
for objects
, else false
.
Javascript Equal operators(== and ===) Examples
Here are some examples of double equal and three equal operator examples
5 == "5" - true;
5 === "5" - false;
"0" == undefined; // true
"0" === undefined; // false
null == undefined; // true
null === undefined; // false
In the above examples,
5==“5”, Comparing number and string, and converted to the same type, i.e numbers, with ==
checks value(5==5) and type(numbers) are same, returns true. 5===“5” return false as both operands are different(integer and string)
javascript Comparision between == vs === operators
Both operators are applied to two operands or variables.
== operator | === operators |
---|---|
Called Comparison operator | Strict comparison operator |
compared two operands or variables, the data type is ignored | compared two operands or variables and data type |
Returns true , if values are equal, false not equal | Returns true , if values and types are equal, false both not equal |
duration | time in milliseconds shown before disappearing from the page |
type coercion before comparison | type coercion ignored before comparison |