Left shift assignment (<<=) - JavaScript 编辑

The left shift assignment operator (<<=) moves the specified amount of bits to the left and assigns the result to the variable.

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Syntax

Operator: x <<= y
Meaning:  x   = x << y

Examples

Using left shift assignment

let a = 5;
// 00000000000000000000000000000101

a <<= 2; // 20
// 00000000000000000000000000010100

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• Assignment operators in the JS guide
• Left shift operator