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• 句法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

Map() 构造函数 creates Map 对象。

句法

new Map([iterable])
					

参数

iterable

Array or other iterable object whose elements are key-value pairs. (For example, arrays with two elements, such as [[ 1, 'one' ],[ 2, 'two' ]] .) Each key-value pair is added to the new Map .

范例

Creating a new Map

let myMap = new Map([
  [1, 'one'],
  [2, 'two'],
  [3, 'three'],
])
					

规范

规范
ECMAScript (ECMA-262) The definition of 'Map constructor' 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
Map() 构造函数	Chrome 38	Edge 12	Firefox 13	IE 11	Opera 25	Safari 8	WebView Android 38	Chrome Android 38	Firefox Android 14	Opera Android 25	Safari iOS 8	Samsung Internet Android 3.0	nodejs 0.12 0.12 0.10 Disabled Disabled From version 0.10: this feature is behind the --harmony runtime flag.
new Map(iterable)	Chrome 38	Edge 12	Firefox 13	IE No	Opera 25	Safari 9	WebView Android 38	Chrome Android 38	Firefox Android 14	Opera Android 25	Safari iOS 9	Samsung Internet Android 3.0	nodejs 0.12
Map() without new throws	Chrome 38	Edge 12	Firefox 42	IE 11	Opera 25	Safari 9	WebView Android 38	Chrome Android 38	Firefox Android 42	Opera Android 25	Safari iOS 9	Samsung Internet Android 3.0	nodejs 0.12
new Map(null)	Chrome 38	Edge 12	Firefox 37	IE 11	Opera 25	Safari 9	WebView Android 38	Chrome Android 38	Firefox Android 37	Opera Android 25	Safari iOS 9	Samsung Internet Android 3.0	nodejs 0.12 0.12 0.10 Disabled Disabled From version 0.10: this feature is behind the --harmony runtime flag.

图例

完整支持

完整支持

不支持

不支持

用户必须明确启用此特征。

用户必须明确启用此特征。

另请参阅

• Set
• WeakMap
• WeakSet

元数据

• 最后修改： May 8, 2020

相关话题

1. 标准内置对象
2. Map
3. 特性
   1. Map.prototype.size
   2. Map.prototype[@@toStringTag]
   3. get Map[@@species]
4. 方法
   1. Map.prototype.clear()
   2. Map.prototype.delete()
   3. Map.prototype.entries()
   4. Map.prototype.forEach()
   5. Map.prototype.get()
   6. Map.prototype.has()
   7. Map.prototype.keys()
   8. Map.prototype.set()
   9. Map.prototype.values()
   10. Map.prototype[@@iterator]()
5. 继承：
6. Function
7. 特性
   1. Function.arguments
   2. Function.caller
   3. Function.displayName
   4. Function.length
   5. Function.name
8. 方法
   1. Function.prototype.apply()
   2. Function.prototype.bind()
   3. Function.prototype.call()
   4. Function.prototype.toSource()
   5. Function.prototype.toString()
9. Object
10. 特性
    1. Object.prototype.__proto__
    2. Object.prototype.constructor
11. 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()