@@iterator 属性和 Array.prototype.values() 属性的初始值均为同一个函数对象。

语法

arr[Symbol.iterator]()

返回值

数组的 iterator 方法,默认情况下与 values() 返回值相同

示例

使用 for...of 循环进行迭代

var arr = ['w', 'y', 'k', 'o', 'p'];
var eArr = arr[Symbol.iterator]();
// 您的浏览器必须支持for...of循环
// 以及let —— 将变量作用域限定在 for 循环中
for (let letter of eArr) {
  console.log(letter);
}

另一种迭代方式

var arr = ['w', 'y', 'k', 'o', 'p'];
var eArr = arr[Symbol.iterator]();
console.log(eArr.next().value); // w
console.log(eArr.next().value); // y
console.log(eArr.next().value); // k
console.log(eArr.next().value); // o
console.log(eArr.next().value); // p

规范

规范名称 规范状态 备注
ECMAScript 2015 (6th Edition, ECMA-262)
Array.prototype[@@iterator]()
Standard 首次定义
ECMAScript Latest Draft (ECMA-262)
Array.prototype[@@iterator]()
Draft  

浏览器兼容性

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
@@iteratorChrome Full support 38Edge Full support 12Firefox Full support 36
Full support 36
No support 27 — 36
Notes Alternate Name
Notes A placeholder property named @@iterator is used.
Alternate Name Uses the non-standard name: @@iterator
No support 17 — 27
Notes Alternate Name
Notes A placeholder property named iterator is used.
Alternate Name Uses the non-standard name: iterator
IE No support NoOpera Full support 25Safari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile ? Firefox Android Full support 36
Full support 36
No support 27 — 36
Notes Alternate Name
Notes A placeholder property named @@iterator is used.
Alternate Name Uses the non-standard name: @@iterator
No support 17 — 27
Notes Alternate Name
Notes A placeholder property named iterator is used.
Alternate Name Uses the non-standard name: iterator
Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support 0.12

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
See implementation notes.
See implementation notes.
Uses a non-standard name.
Uses a non-standard name.

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