Question

42 viewsNovember 29, 2024

0

codification school November 29, 2024 0 Comments

What is the difference between == and ===?

codification school Changed status to publish November 29, 2024

1 Answer

score 0 · Answer 1 · 2024-11-29T16:00:16+00:00

1. `==` (Equality Operator)

Type Coercion: Converts the operands to the same type before comparing them.
Purpose: Checks for value equality after implicit type conversion.

Example:

console.log(5 == "5");  // true (string "5" is converted to number 5)
console.log(null == undefined); // true (both are treated as loosely equal)
console.log(0 == false); // true (false is converted to 0)

2. `===` (Strict Equality Operator)

No Type Coercion: Compares both the value and the type without converting them.
Purpose: Checks for strict equality, ensuring both value and type match.

Example:

console.log(5 === "5");  // false (different types: number and string)
console.log(null === undefined); // false (different types)
console.log(0 === false); // false (number vs. boolean)

Key Points:

Feature	`==` (Equality)	`===` (Strict Equality)
Type Conversion	Yes	No
Value Comparison	After coercion	Direct
Use Case	When types can differ	When type and value must match

Best Practice:

Use === unless you have a specific reason to allow type coercion. This ensures fewer bugs and makes the code more predictable.

Example of safer usage:

const userInput = "42";
const expectedValue = 42;

if (userInput === expectedValue) {
    console.log("Values and types match!");
} else {
    console.log("Mismatch!");
}

1 Answer

1. == (Equality Operator)

2. === (Strict Equality Operator)

Key Points:

Best Practice:

Unlock your feature login with Facebook or Google

1. `==` (Equality Operator)

2. `===` (Strict Equality Operator)