在此页

• 构造函数
• 静态特性
• 静态方法
• 实例特性
• 实例方法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

Float64Array typed array represents an array of 64-bit floating point numbers (corresponding to the C double data type) 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).

构造函数

Float64Array()

创建新的 Float64Array 对象。

静态特性

Float64Array.BYTES_PER_ELEMENT

Returns a number value of the element size. 8 in the case of an Float64Array .

Float64Array.name

Returns the string value of the constructor name. In the case of the Float64Array type: "Float64Array".

静态方法

Float64Array.from()

创建新的 Float64Array from an array-like or iterable object. See also Array.from() .

Float64Array.of()

创建新的 Float64Array with a variable number of arguments. See also Array.of() .

实例特性

Float64Array.prototype.buffer

返回 ArrayBuffer referenced by the Float64Array Fixed at construction time and thus read only .

Float64Array.prototype.byteLength

Returns the length (in bytes) of the Float64Array from the start of its ArrayBuffer . Fixed at construction time and thus read only.

Float64Array.prototype.byteOffset

Returns the offset (in bytes) of the Float64Array from the start of its ArrayBuffer . Fixed at construction time and thus read only.

Float64Array.prototype.length

Returns the number of elements hold in the Float64Array . Fixed at construction time and thus read only.

实例方法

Float64Array.prototype.copyWithin()

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

Float64Array.prototype.entries()

返回新的 Array Iterator object that contains the key/value pairs for each index in the array. See also Array.prototype.entries() .

Float64Array.prototype.every()

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

Float64Array.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() .

Float64Array.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() .

Float64Array.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() .

Float64Array.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() .

Float64Array.prototype.forEach()

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

Float64Array.prototype.includes()

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

Float64Array.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() .

Float64Array.prototype.join()

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

Float64Array.prototype.keys()

返回新的 Array Iterator that contains the keys for each index in the array. See also Array.prototype.keys() .

Float64Array.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() .

Float64Array.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() .

Float64Array.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() .

Float64Array.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() .

Float64Array.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() .

Float64Array.prototype.set()

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

Float64Array.prototype.slice()

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

Float64Array.prototype.some()

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

Float64Array.prototype.sort()

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

Float64Array.prototype.subarray()

返回新的 Float64Array from the given start and end element index.

Float64Array.prototype.values()

返回新的 Array Iterator object that contains the values for each index in the array. See also Array.prototype.values() .

Float64Array.prototype.toLocaleString()

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

Float64Array.prototype.toString()

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

Float64Array.prototype[@@iterator]()

返回新的 Array Iterator object that contains the values for each index in the array.

范例

Different ways to create a Float64Array

// From a length
var float64 = new Float64Array(2);
float64[0] = 42;
console.log(float64[0]); // 42
console.log(float64.length); // 2
console.log(float64.BYTES_PER_ELEMENT); // 8
// From an array
var arr = new Float64Array([21,31]);
console.log(arr[1]); // 31
// From another TypedArray
var x = new Float64Array([21, 31]);
var y = new Float64Array(x);
console.log(y[0]); // 21
// From an ArrayBuffer
var buffer = new ArrayBuffer(32);
var z = new Float64Array(buffer, 0, 4);
// From an iterable
var iterable = function*(){ yield* [1,2,3]; }();
var float64 = new Float64Array(iterable);
// Float64Array[1, 2, 3]
						

规范

规范
ECMAScript (ECMA-262) The definition of 'TypedArray constructors' in that specification.

浏览器兼容性

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. 更新 GitHub 上的兼容性数据

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
Float64Array	Chrome 7	Edge 12	Firefox 4	IE 10	Opera 11.6	Safari 5.1	WebView Android 4	Chrome Android 18	Firefox Android 4	Opera Android 12	Safari iOS 4.2	Samsung Internet Android 1.0	nodejs 0.10
Float64Array() 构造函数	Chrome 7	Edge 12	Firefox 4	IE 10	Opera 11.6	Safari 5.1	WebView Android 4	Chrome Android 18	Firefox Android 4	Opera Android 12	Safari iOS 4.2	Samsung Internet Android 1.0	nodejs 0.10

图例

完整支持

完整支持

另请参阅

• JavaScript 类型数组
• ArrayBuffer
• DataView

元数据

• 最后修改： May 8, 2020

相关话题

1. 标准内置对象
2. TypedArray
3. 特性
   1. TypedArray.BYTES_PER_ELEMENT
   2. TypedArray.name
   3. TypedArray.prototype.buffer
   4. TypedArray.prototype.byteLength
   5. TypedArray.prototype.byteOffset
   6. TypedArray.prototype.length
   7. get TypedArray[@@species]
4. 方法
   1. TypedArray.from()
   2. TypedArray.of()
   3. TypedArray.prototype.copyWithin()
   4. TypedArray.prototype.entries()
   5. TypedArray.prototype.every()
   6. TypedArray.prototype.fill()
   7. TypedArray.prototype.filter()
   8. TypedArray.prototype.find()
   9. TypedArray.prototype.findIndex()
   10. TypedArray.prototype.forEach()
   11. TypedArray.prototype.includes()
   12. TypedArray.prototype.indexOf()
   13. TypedArray.prototype.join()
   14. TypedArray.prototype.keys()
   15. TypedArray.prototype.lastIndexOf()
   16. TypedArray.prototype.map()
   17. TypedArray.prototype.reduce()
   18. TypedArray.prototype.reduceRight()
   19. TypedArray.prototype.reverse()
   20. TypedArray.prototype.set()
   21. TypedArray.prototype.slice()
   22. TypedArray.prototype.some()
   23. TypedArray.prototype.sort()
   24. TypedArray.prototype.subarray()
   25. TypedArray.prototype.toLocaleString()
   26. TypedArray.prototype.toString()
   27. TypedArray.prototype.values()
   28. TypedArray.prototype[@@iterator]()
5. 相关页面：
6. Int8Array
7. Uint8Array
8. Uint8ClampedArray
9. Int16Array
10. Uint16Array
11. Int32Array
12. Uint32Array
13. Float32Array
14. Float64Array
15. BigInt64Array
16. BigUint64Array
17. 继承：
18. Function
19. 特性
    1. Function.arguments
    2. Function.caller
    3. Function.displayName
    4. Function.length
    5. Function.name
20. 方法
    1. Function.prototype.apply()
    2. Function.prototype.bind()
    3. Function.prototype.call()
    4. Function.prototype.toSource()
    5. Function.prototype.toString()
21. Object
22. 特性
    1. Object.prototype.__proto__
    2. Object.prototype.constructor
23. 方法
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.valueOf()
    12. Object.setPrototypeOf()