Uint8ClampedArray

Типизированный массив Uint8ClampedArray —  это массив,  служащий для хранения 8-битных беззнаковых чисел, обрезаемых до диапазона от 0 до 255. Если значение меньше 0, то оно будет приведено к 0 , и к 255, если оно больше 255. Числа с плавающей точкой округляются с помощью математического округления. Массив инициализируется нулями. После того как значение установлено, вы можете ссылаться на него с помощью методов объекта или через стандартный синтаксис массивов (то есть, брать значения с помощью квадратных скобок). 

Syntax

new Uint8ClampedArray(length);
new Uint8ClampedArray(typedArray);
new Uint8ClampedArray(object);
new Uint8ClampedArray(buffer [, byteOffset [, length]]);

Для более подробной информации, смотрите TypedArray.

Properties

Uint8ClampedArray.BYTES_PER_ELEMENT
Возвращает размер элемента в байтах. Для Uint8ClampedArray оно равно 1.
Uint8ClampedArray.length
Static length property whose value is 3. For the actual length (number of elements), see Uint8ClampedArray.prototype.length (en-US).
Uint8ClampedArray.name (en-US)
Returns the string value of the constructor name. In the case of the Uint8ClampedArray type: "Uint8ClampedArray".
Uint8ClampedArray.prototype
Prototype for the TypedArray objects.

Methods

Uint8ClampedArray.from() (en-US)
Creates a new Uint8ClampedArray from an array-like or iterable object. See also Array.from().
Uint8ClampedArray.of() (en-US)
Creates a new Uint8ClampedArray with a variable number of arguments. See also Array.of().

Uint8ClampedArray prototype

All Uint8ClampedArray objects inherit from %TypedArray%.prototype.

Properties

Uint8ClampedArray.prototype.constructor
Returns the function that created an instance's prototype. This is the Uint8ClampedArray constructor by default.
Uint8ClampedArray.prototype.buffer (en-US) Только для чтения
Returns the ArrayBuffer referenced by the Uint8ClampedArray Fixed at construction time and thus read only.
Uint8ClampedArray.prototype.byteLength (en-US) Только для чтения
Returns the length (in bytes) of the Uint8ClampedArray from the start of its ArrayBuffer. Fixed at construction time and thus read only.
Uint8ClampedArray.prototype.byteOffset (en-US) Только для чтения
Returns the offset (in bytes) of the Uint8ClampedArray from the start of its ArrayBuffer. Fixed at construction time and thus read only.
Uint8ClampedArray.prototype.length (en-US) Только для чтения
Returns the number of elements hold in the UintClamped8Array. Fixed at construction time and thus read only.

Methods

Uint8ClampedArray.prototype.copyWithin() (en-US)
Copies a sequence of array elements within the array. See also Array.prototype.copyWithin().
Uint8ClampedArray.prototype.entries() (en-US)
Returns a new Array Iterator object that contains the key/value pairs for each index in the array. See also Array.prototype.entries().
Uint8ClampedArray.prototype.every() (en-US)
Tests whether all elements in the array pass the test provided by a function. See also Array.prototype.every().
Uint8ClampedArray.prototype.fill() (en-US)
Fills all the elements of an array from a start index to an end index with a static value. See also Array.prototype.fill().
Uint8ClampedArray.prototype.filter() (en-US)
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().
Uint8ClampedArray.prototype.find() (en-US)
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().
Uint8ClampedArray.prototype.findIndex() (en-US)
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().
Uint8ClampedArray.prototype.forEach() (en-US)
Calls a function for each element in the array. See also Array.prototype.forEach().
Uint8ClampedArray.prototype.includes() (en-US) Это экспериментальное API, которое не должно использоваться в рабочем коде.
Determines whether a typed array includes a certain element, returning true or false as appropriate. See also Array.prototype.includes().
Uint8ClampedArray.prototype.indexOf() (en-US)
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().
Uint8ClampedArray.prototype.join()
Joins all elements of an array into a string. See also Array.prototype.join().
Uint8ClampedArray.prototype.keys() (en-US)
Returns a new Array Iterator that contains the keys for each index in the array. See also Array.prototype.keys().
Uint8ClampedArray.prototype.lastIndexOf() (en-US)
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().
Uint8ClampedArray.prototype.map() (en-US)
Creates a new array with the results of calling a provided function on every element in this array. See also Array.prototype.map().
Uint8ClampedArray.prototype.move() Это API не было стандартизировано. Не реализовано
Former non-standard version of Uint8ClampedArray.prototype.copyWithin() (en-US).
Uint8ClampedArray.prototype.reduce() (en-US)
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().
Uint8ClampedArray.prototype.reduceRight() (en-US)
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().
Uint8ClampedArray.prototype.reverse() (en-US)
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().
Uint8ClampedArray.prototype.set()
Stores multiple values in the typed array, reading input values from a specified array.
Uint8ClampedArray.prototype.slice() (en-US)
Extracts a section of an array and returns a new array. See also Array.prototype.slice().
Uint8ClampedArray.prototype.some() (en-US)
Returns true if at least one element in this array satisfies the provided testing function. See also Array.prototype.some().
Uint8ClampedArray.prototype.sort() (en-US)
Sorts the elements of an array in place and returns the array. See also Array.prototype.sort().
Uint8ClampedArray.prototype.subarray() (en-US)
Returns a new Uint8ClampedArray from the given start and end element index.
Uint8ClampedArray.prototype.values() (en-US)
Returns a new Array Iterator object that contains the values for each index in the array. See also Array.prototype.values().
Uint8ClampedArray.prototype.toLocaleString() (en-US)
Returns a localized string representing the array and its elements. See also Array.prototype.toLocaleString().
Uint8ClampedArray.prototype.toString() (en-US)
Returns a string representing the array and its elements. See also Array.prototype.toString().
Uint8ClampedArray.prototype[@@iterator]() (en-US)
Returns a new Array Iterator object that contains the values for each index in the array.

Examples

// From a length
var uintc8 = new Uint8ClampedArray(2);
uintc8[0] = 42;
uintc8[1] = 1337;
console.log(uintc8[0]); // 42
console.log(uintc8[1]); // 255 (clamped)
console.log(uintc8.length); // 2
console.log(uintc8.BYTES_PER_ELEMENT); // 1

// From an array
var arr = new Uint8ClampedArray([21,31]);
console.log(arr[1]); // 31

// From another TypedArray
var x = new Uint8ClampedArray([21, 31]);
var y = new Uint8ClampedArray(x);
console.log(y[0]); // 21

// From an ArrayBuffer
var buffer = new ArrayBuffer(8);
var z = new Uint8ClampedArray(buffer, 1, 4);

Specifications

Specification Status Comment
Typed Array Specification Устаревшая Superseded by ECMAScript 6.
ECMAScript 2015 (6th Edition, ECMA-262)
Определение 'TypedArray constructors' в этой спецификации.
Стандарт Initial definition in an ECMA standard. Specified that new is required.
ECMAScript (ECMA-262)
Определение 'TypedArray constructors' в этой спецификации.
Живой стандарт  

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help! (en-US)

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 7.0 4.0 (2) 11 (as of KB2929437) 11.6 5.1
new is required ? 44 (44) ? ? ?
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 4.0 (Да) 4.0 (2) (Да) 11.6 4.2
new is required ? ? 44.0 (44) ? ? ?

Compatibility notes

Starting with ECMAScript 2015 (ES6), Uint8ClampedArray constructors require to be constructed with a new operator. Calling a Uint8ClampedArray constructor as a function without new, will throw a TypeError from now on.

var dv = Uint8ClampedArray([1, 2, 3]);
// TypeError: calling a builtin Uint8ClampedArray constructor
// without new is forbidden
var dv = new Uint8ClampedArray([1, 2, 3]);

See also