Uint8Array

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.

Uint8Array 类型数组表示 8 位无符号整数数组。除非明确提供初始化数据,否则内容将初始化为 0。一旦建立,你可以使用对象的方法或使用标准数组索引语法(即使用括号表示法)来引用数组中的元素。

¥The Uint8Array typed array represents an array of 8-bit unsigned integers. The contents are initialized to 0 unless initialization data is explicitly provided. Once established, you can reference elements in the array using the object's methods, or using standard array index syntax (that is, using bracket notation).

Uint8Array 是隐藏 TypedArray 类的子类。

¥Uint8Array is a subclass of the hidden TypedArray class.

构造函数

¥Constructor

Uint8Array()

创建一个新的 Uint8Array 对象。

静态属性

¥Static properties

还从其父级 TypedArray 继承静态属性。

¥Also inherits static properties from its parent TypedArray.

Uint8Array.BYTES_PER_ELEMENT

返回元素大小的数值。1Uint8Array 的情况下。

静态方法

¥Static methods

从其父级 TypedArray 继承静态方法。

¥Inherits static methods from its parent TypedArray.

实例属性

¥Instance properties

还从其父级 TypedArray 继承实例属性。

¥Also inherits instance properties from its parent TypedArray.

这些属性在 Uint8Array.prototype 上定义并由所有 Uint8Array 实例共享。

¥These properties are defined on Uint8Array.prototype and shared by all Uint8Array instances.

Uint8Array.prototype.BYTES_PER_ELEMENT

返回元素大小的数值。如果是 Uint8Array,则为 1

Uint8Array.prototype.constructor

创建实例对象的构造函数。对于 Uint8Array 实例,初始值为 Uint8Array 构造函数。

实例方法

¥Instance methods

从其父级 TypedArray 继承实例方法。

¥Inherits instance methods from its parent TypedArray.

示例

¥Examples

创建 Uint8Array 的不同方法

¥Different ways to create a Uint8Array

js
// From a length
const uint8 = new Uint8Array(2);
uint8[0] = 42;
console.log(uint8[0]); // 42
console.log(uint8.length); // 2
console.log(uint8.BYTES_PER_ELEMENT); // 1

// From an array
const x = new Uint8Array([21, 31]);
console.log(x[1]); // 31

// From another TypedArray
const y = new Uint8Array(x);
console.log(y[0]); // 21

// From an ArrayBuffer
const buffer = new ArrayBuffer(8);
const z = new Uint8Array(buffer, 1, 4);
console.log(z.byteOffset); // 1

// From an iterable
const iterable = (function* () {
  yield* [1, 2, 3];
})();
const uint8FromIterable = new Uint8Array(iterable);
console.log(uint8FromIterable);
// Uint8Array [1, 2, 3]

规范

Specification
ECMAScript Language Specification
# table-49

¥Specifications

浏览器兼容性

BCD tables only load in the browser

¥Browser compatibility

也可以看看