Int32Array

The Int32Array typed array represents an array of twos-complement 32-bit signed integers in the platform byte order. If control over byte order is needed, use DataView instead. The contents are initialized to 0. 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).

语法

new Int32Array(length);
new Int32Array(typedArray);
new Int32Array(object);
new Int32Array(buffer [, byteOffset [, length]]);

For more information about the constructor syntax and the parameters, see TypedArray.

属性

Int32Array.BYTES_PER_ELEMENT

Returns a number value of the element size. 4 in the case of an Int32Array.

Int32Array.length

Static length property whose value is 3. For the actual length (number of elements), see Int32Array.prototype.length.

Int32Array.name

Returns the string value of the constructor name. In the case of the Int32Array type: "Int32Array".

Int32Array.prototype

Prototype for the TypedArray objects.

方法

Int32Array.from()

Creates a new Int32Array from an array-like or iterable object. See also Array.from().

Int32Array.of()

Creates a new Int32Array with a variable number of arguments. See also Array.of().

Int32Array 属性

All Int32Array objects inherit from %TypedArray%.prototype.

属性

Int32Array.prototype.constructor

Returns the function that created an instance's prototype. This is the Int32Array constructor by default.

Int32Array.prototype.buffer 只读

Returns the ArrayBuffer referenced by the Int32Array Fixed at construction time and thus read only.

Int32Array.prototype.byteLength 只读

Returns the length (in bytes) of the Int32Array from the start of its ArrayBuffer. Fixed at construction time and thus read only.

Int32Array.prototype.byteOffset 只读

Returns the offset (in bytes) of the Int32Array from the start of its ArrayBuffer. Fixed at construction time and thus read only.

Int32Array.prototype.length 只读

Returns the number of elements hold in the Int32Array. Fixed at construction time and thus read only.

方法

Int32Array.prototype.copyWithin()

Copies a sequence of array elements within the array. See also Array.prototype.copyWithin().

Int32Array.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().

Int32Array.prototype.every()

Tests whether all elements in the array pass the test provided by a function. See also Array.prototype.every().

Int32Array.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().

Int32Array.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().

Int32Array.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().

Int32Array.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().

Int32Array.prototype.forEach()

Calls a function for each element in the array. See also Array.prototype.forEach().

Int32Array.prototype.includes()

Determines whether a typed array includes a certain element, returning true or false as appropriate. See also Array.prototype.includes().

Int32Array.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().

Int32Array.prototype.join()

Joins all elements of an array into a string. See also Array.prototype.join().

Int32Array.prototype.keys()

Returns a new Array Iterator that contains the keys for each index in the array. See also Array.prototype.keys().

Int32Array.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().

Int32Array.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().

Int32Array.prototype.move() 未实现

Former non-standard version of Int32Array.prototype.copyWithin().

Int32Array.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().

Int32Array.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().

Int32Array.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().

Int32Array.prototype.set()

Stores multiple values in the typed array, reading input values from a specified array.

Int32Array.prototype.slice()

Extracts a section of an array and returns a new array. See also Array.prototype.slice().

Int32Array.prototype.some()

Returns true if at least one element in this array satisfies the provided testing function. See also Array.prototype.some().

Int32Array.prototype.sort()

Sorts the elements of an array in place and returns the array. See also Array.prototype.sort().

Int32Array.prototype.subarray()

Returns a new Int32Array from the given start and end element index.

Int32Array.prototype.values()

Returns a new Array Iterator object that contains the values for each index in the array. See also Array.prototype.values().

Int32Array.prototype.toLocaleString()

Returns a localized string representing the array and its elements. See also Array.prototype.toLocaleString().

Int32Array.prototype.toString()

Returns a string representing the array and its elements. See also Array.prototype.toString().

Int32Array.prototype[@@iterator]()

Returns a new Array Iterator object that contains the values for each index in the array.

例子

// From a length
var int32 = new Int32Array(2);
int32[0] = 42;
console.log(int32[0]); // 42
console.log(int32.length); // 2
console.log(int32.BYTES_PER_ELEMENT); // 4
// From an array
var arr = new Int32Array([21,31]);
console.log(arr[1]); // 31
// From another TypedArray
var x = new Int32Array([21, 31]);
var y = new Int32Array(x);
console.log(y[0]); // 21
// From an ArrayBuffer
var buffer = new ArrayBuffer(16);
var z = new Int32Array(buffer, 0, 4);

详细描述

浏览器兼容性

兼容性说明

Starting with ECMAScript 2015 (ES6), In32Array constructors require to be constructed with a new operator. Calling a Int32Array constructor as a function without new, will throw a TypeError from now on.

var dv = Int32Array([1, 2, 3]);
// TypeError: calling a builtin Int32Array constructor
// without new is forbidden

var dv = new Int32Array([1, 2, 3]);

参见

• JavaScript typed arrays
• ArrayBuffer
• DataView