赋值(=)
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.
简单赋值运算符(=
)用于给变量赋值。赋值表达式本身的值为要赋值的值。为了将一个值赋给多个变量,可以链式使用赋值运算符。
尝试一下
let x = 2;
const y = 3;
console.log(x);
// Expected output: 2
console.log((x = y + 1)); // 3 + 1
// Expected output: 4
console.log((x = x * y)); // 4 * 3
// Expected output: 12
语法
js
x = y
示例
简单赋值和链式赋值
js
// 假设已经存在以下变量
// x = 5
// y = 10
// z = 25
x = y; // x 为 10
x = y = z; // x, y 都为 25
规范
Specification |
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ECMAScript® 2025 Language Specification # sec-assignment-operators |
浏览器兼容性
Report problems with this compatibility data on GitHubdesktop | mobile | server | ||||||||||||
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Assignment ( x = y ) |
Legend
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- Full support
- Full support
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