Int8Array

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.

Объект Int8Array представляет типизированный массив 8-разрядных целых значений. Содержимое инициализируется значением 0. Создав экземпляр Int8Array, возможно получить доступ к элементам массива, используя методы объекта или стандартный синтаксис доступа к элементу массива по его индексу (с помощью скобочной нотации).

Syntax

new Int8Array(); // new in ES2017
new Int8Array(length);
new Int8Array(typedArray);
new Int8Array(object);
new Int8Array(buffer [, byteOffset [, length]]);

Для более детальной информации о синтаксисе конструктора смотрите TypedArray.

Properties

Int8Array.BYTES_PER_ELEMENT: Возвращает числовое значение размера элемента массива. 1 в случае с Int8Array.
Int8Array.length: Статическая длина конструктора Int8Array, всегда равна 3 (т.к. конструктор принимает до 3 аргументов). Чтобы узнать длину созданного массива, see Int8Array.prototype.length.
Int8Array.name: Возвращает строчное значение имени конструктора. В случае с Int8Array: "Int8Array".
Int8Array.prototype: Прототип для TypedArray objects.

Methods

Int8Array.from(): Creates a new Int8Array from an array-like or iterable object. See also Array.from().
Int8Array.of(): Creates a new Int8Array with a variable number of arguments. See also Array.of().

`Int8Array` prototype

All Int8Array objects inherit from %TypedArray%.prototype.

Properties

Int8Array.prototype.constructor: Returns the function that created an instance's prototype. This is the Int8Array constructor by default.
Int8Array.prototype.buffer Только для чтения: Returns the ArrayBuffer referenced by the Int8Array Fixed at construction time and thus read only.
Int8Array.prototype.byteLength Только для чтения: Returns the length (in bytes) of the Int8Array from the start of its ArrayBuffer. Fixed at construction time and thus read only.
Int8Array.prototype.byteOffset Только для чтения: Returns the offset (in bytes) of the Int8Array from the start of its ArrayBuffer. Fixed at construction time and thus read only.
Int8Array.prototype.length Только для чтения: Returns the number of elements hold in the Int8Array. Fixed at construction time and thus read only.

Methods

Int8Array.prototype.copyWithin(): Copies a sequence of array elements within the array. See also Array.prototype.copyWithin().
Int8Array.prototype.entries(): Returns a new Array Iterator object that contains the key/value pairs for each index in the array. See also Array.prototype.entries().
Int8Array.prototype.every(): Tests whether all elements in the array pass the test provided by a function. See also Array.prototype.every().
Int8Array.prototype.fill(): Fills all the elements of an array from a start index to an end index with a static value. See also Array.prototype.fill().
Int8Array.prototype.filter(): Creates a new array with all of the elements of this array for which the provided filtering function returns true. See also Array.prototype.filter().
Int8Array.prototype.find(): Returns the found value in the array, if an element in the array satisfies the provided testing function or undefined if not found. See also Array.prototype.find().
Int8Array.prototype.findIndex(): Returns the found index in the array, if an element in the array satisfies the provided testing function or -1 if not found. See also Array.prototype.findIndex().
Int8Array.prototype.forEach(): Calls a function for each element in the array. See also Array.prototype.forEach().
Int8Array.prototype.includes() Экспериментальная возможность: Determines whether a typed array includes a certain element, returning true or false as appropriate. See also Array.prototype.includes().
Int8Array.prototype.indexOf(): Returns the first (least) index of an element within the array equal to the specified value, or -1 if none is found. See also Array.prototype.indexOf().
Int8Array.prototype.join(): Joins all elements of an array into a string. See also Array.prototype.join().
Int8Array.prototype.keys(): Returns a new Array Iterator that contains the keys for each index in the array. See also Array.prototype.keys().
Int8Array.prototype.lastIndexOf(): Returns the last (greatest) index of an element within the array equal to the specified value, or -1 if none is found. See also Array.prototype.lastIndexOf().
Int8Array.prototype.map(): Creates a new array with the results of calling a provided function on every element in this array. See also Array.prototype.map().
Int8Array.prototype.reduce(): Apply a function against an accumulator and each value of the array (from left-to-right) as to reduce it to a single value. See also Array.prototype.reduce().
Int8Array.prototype.reduceRight(): Apply a function against an accumulator and each value of the array (from right-to-left) as to reduce it to a single value. See also Array.prototype.reduceRight().
Int8Array.prototype.reverse(): Reverses the order of the elements of an array — the first becomes the last, and the last becomes the first. See also Array.prototype.reverse().
Int8Array.prototype.set(): Stores multiple values in the typed array, reading input values from a specified array.
Int8Array.prototype.slice(): Extracts a section of an array and returns a new array. See also Array.prototype.slice().
Int8Array.prototype.some(): Returns true if at least one element in this array satisfies the provided testing function. See also Array.prototype.some().
Int8Array.prototype.sort(): Sorts the elements of an array in place and returns the array. See also Array.prototype.sort().
Int8Array.prototype.subarray(): Returns a new Int8Array from the given start and end element index.
Int8Array.prototype.values(): Returns a new Array Iterator object that contains the values for each index in the array. See also Array.prototype.values().
Int8Array.prototype.toLocaleString(): Returns a localized string representing the array and its elements. See also Array.prototype.toLocaleString().
Int8Array.prototype.toString(): Returns a string representing the array and its elements. See also Array.prototype.toString().
Int8Array.prototype[@@iterator](): Returns a new Array Iterator object that contains the values for each index in the array.

Examples

Different ways to create an Int8Array:

// From a length
var int8 = new Int8Array(2);
int8[0] = 42;
console.log(int8[0]); // 42
console.log(int8.length); // 2
console.log(int8.BYTES_PER_ELEMENT); // 1

// From an array
var arr = new Int8Array([21, 31]);
console.log(arr[1]); // 31

// From another TypedArray
var x = new Int8Array([21, 31]);
var y = new Int8Array(x);
console.log(y[0]); // 21

// From an ArrayBuffer
var buffer = new ArrayBuffer(8);
var z = new Int8Array(buffer, 1, 4);

// From an iterable
var iterable = (function* () {
  yield* [1, 2, 3];
})();
var int8 = new Int8Array(iterable);
// Int8Array[1, 2, 3]

Спецификации

Specification
ECMAScript Language Specification # table-49

Совместимость с браузерами

BCD tables only load in the browser

Compatibility notes

Starting with ECMAScript 2015, Int8Array constructors require to be constructed with a new operator. Calling a Int8Array constructor as a function without new, will throw a TypeError from now on.

var dv = Int8Array([1, 2, 3]);
// TypeError: calling a builtin Int8Array constructor
// without new is forbidden

var dv = new Int8Array([1, 2, 3]);