乗算代入 (*=)
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
乗算代入演算子 (*=
) は、変数に右のオペランドの値を乗算し、結果を変数に代入します。
試してみましょう
let a = 2;
console.log((a *= 3));
// Expected output: 6
console.log((a *= "hello"));
// Expected output: NaN
構文
js
x *= y; // x = x * y
例
乗算代入の使用
js
// 次の変数を想定
// bar = 5
bar *= 2; // 10
bar *= "foo"; // NaN
仕様書
Specification |
---|
ECMAScript® 2025 Language Specification # sec-assignment-operators |
ブラウザーの互換性
Report problems with this compatibility data on GitHubdesktop | mobile | server | ||||||||||||
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Multiplication assignment ( x *= y ) |
Legend
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- Full support
- Full support
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.