JavaScript Assignment

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;

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 Division Assignment Operator divides a variable.

Division 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;

String Assignment

Two assignment operators can assign values to strings:

The Simple Assignment Operator assigns a simple value to a string.

The Addition Assignment Operator adds a value to a string.

The = Operator

The Simple Assignment Operator assigns a value to a variable.

String Assignment

let text = "Hello";

The += Operator

The Addition Assignment Operator Can also be used to add strings.

Addition Assignment Example

let text = "Hello";
text += " World";

The &&= Operator

The Logical AND assignment operator is used between two values.

If the first value is true, the second value is assigned.

Logical AND Assignment Examples

let x = true;

let y = x &&= 10;

The ||= Operator

The Logical OR assignment operator is used between two values.

If the first value is false, the second value is assigned.

Logical OR Assignment Examples

let x = false;

let y = x ||= 10;

The ??= Operator

The Nullish coalescing assignment operator is used between two values.

If the first value is undefined or null, the second value is assigned.

Nullish Coalescing Assignment Examples

let x;

x ??= 10;

Quick Reference

The 8 FALSY Values

These are TRUTHY

It is a common mistake to think these are falsy, but they actually evaluate to true:

The Spread (...) Operator

The ... operator splits iterables into individual elements.

Example

let text = "12345";

let min = Math.min(...text);

let max = Math.max(...text);