Atomics
.xor() 静态方法会在数组中给定位置进行一次按位异或操作,并返回该位置的旧值。这个原子操作保证在修改后的值被写回之前不会发生其他写操作。
The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.
语法
Atomics.xor(typedArray, index, value)
参数
-
typedArray -
一个共享的整型 typed array。例如
Int8Array,Uint8Array,Int16Array,Uint16Array,Int32Array, 或者Uint32Array. -
index -
typedArray中需要进行按位异或的索引位置。 -
value - 要进行按位异或的数字。
返回值
给定位置的旧值 (typedArray[index])。
异常
- 假如
typedArray不是允许的整型之一,则抛出TypeError。 - 假如
typedArray不是一个共享的整型 typed array,则抛出TypeError。 - 如果
index超出了typedArray的边界,则抛出RangeError。
描述
如果a和b不同,则按位异或操作产生1。异或操作的真值表如下:
a |
b |
a ^ b |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
例如,按位异或 5 & 1 将返回 0100,而 0100 是十进制为 4 。
5 0101 1 0001 ---- 4 0100
例子
const sab = new SharedArrayBuffer(1024); const ta = new Uint8Array(sab); ta[0] = 5; Atomics.xor(ta, 0, 1); // returns 5, the old value Atomics.load(ta, 0); // 4
规范
| Specification | Status | Comment |
|---|---|---|
| ECMAScript Latest Draft (ECMA-262) Atomics.xor |
Draft | Initial definition in ES2017. |
浏览器支持
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.
Update compatibility data on GitHub
| Desktop | Mobile | Server | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
xor |
Chrome Full support 68
|
Edge No support 16 — 17
|
Firefox Full support 57
|
IE No support No | Opera No support No | Safari No support 10.1 — ? | WebView Android No support 60 — 63
|
Chrome Android No support 60 — 63
|
Firefox Android Full support 57
|
Opera Android No support No | Safari iOS No support No | Samsung Internet Android No support No
|
nodejs Full support 8.10.0 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.
- See implementation notes.
- User must explicitly enable this feature.
- User must explicitly enable this feature.