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• 句法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

values() method returns a new Array Iterator object that contains the values for each index in the array.

句法

arr.values()
					

返回值

A new Array iterator object.

范例

Iteration using for...of loop

var arr = ['a', 'b', 'c', 'd', 'e'];
var iterator = arr.values();
for (let letter of iterator) {
  console.log(letter);
}  //"a" "b" "c" "d" "e"
					

Array.prototype.values is default implementation of Array.prototype[Symbol.iterator] .

Array.prototype.values === Array.prototype[Symbol.iterator]      //true
					

Iteration using .next()

var arr = ['a', 'b', 'c', 'd', 'e'];
var iterator = arr.values();
iterator.next();               // Object { value: "a", done: false }
iterator.next().value;         // "b"
iterator.next()["value"];      // "c"
iterator.next();               // Object { value: "d", done: false }
iterator.next();               // Object { value: "e", done: false }
iterator.next();               // Object { value: undefined, done: true }
iteraror.next().value;         // undefined
					

One-use: the array iterator object is one use or temporary object

example:

var arr = ['a', 'b', 'c', 'd', 'e'];
 var iterator = arr.values();
 for (let letter of iterator) {
 console.log(letter);
} //"a" "b" "c" "d" "e"
for (let letter of iterator) {
console.log(letter);
} // undefined
					

reason: When next().done=true or currentIndex>length the for..of loop ends. See Iteration protocols.

Value : there are no values stored in the array Iterator object; instead it stores the address of the array used in its creation and so depends on the values stored in that array.

var arr = ['a', 'b', 'c', 'd', 'e'];
var iterator = arr.values();
console.log(iterator);        // Array Iterator {  }
iterator.next().value;        // "a"
arr[1]='n';
iterator.next().value;        //  "n"
					

if the values in the array changed the array iterator object values change too.

TODO : please write about why we need it, use cases.

规范

规范
ECMAScript (ECMA-262) The definition of 'Array.prototype.values' in that specification.

浏览器兼容性

The compatibility table in 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
值	Chrome 66	Edge 12	Firefox 60	IE No	Opera 53	Safari 9	WebView Android 66	Chrome Android 66	Firefox Android 60	Opera Android 47	Safari iOS 9	Samsung Internet Android 9.0	nodejs 10.9.0 10.9.0 6.5.0 Disabled --harmony-array-prototype-values flag is required; the --harmony flag is not sufficient in this case. Disabled From version 6.5.0: this feature is behind the --harmony-array-prototype-values runtime flag. 0.12 — 4.0.0

图例

完整支持

完整支持

不支持

不支持

见实现注意事项。

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

• Array.prototype.keys()
• Array.prototype.entries()
• Array.prototype.forEach()
• Array.prototype.every()
• Array.prototype.some()

元数据

• 最后修改： Jun 28, 2020

相关话题

1. 标准内置对象
2. Array
3. 特性
   1. Array.prototype.length
   2. Array.prototype[@@unscopables]
4. 方法
   1. Array.from()
   2. Array.isArray()
   3. Array.of()
   4. Array.prototype.concat()
   5. Array.prototype.copyWithin()
   6. Array.prototype.entries()
   7. Array.prototype.every()
   8. Array.prototype.fill()
   9. Array.prototype.filter()
   10. Array.prototype.find()
   11. Array.prototype.findIndex()
   12. Array.prototype.flat()
   13. Array.prototype.flatMap()
   14. Array.prototype.forEach()
   15. Array.prototype.includes()
   16. Array.prototype.indexOf()
   17. Array.prototype.join()
   18. Array.prototype.keys()
   19. Array.prototype.lastIndexOf()
   20. Array.prototype.map()
   21. Array.prototype.pop()
   22. Array.prototype.push()
   23. Array.prototype.reduce()
   24. Array.prototype.reduceRight()
   25. Array.prototype.reverse()
   26. Array.prototype.shift()
   27. Array.prototype.slice()
   28. Array.prototype.some()
   29. Array.prototype.sort()
   30. Array.prototype.splice()
   31. Array.prototype.toLocaleString()
   32. Array.prototype.toSource()
   33. Array.prototype.toString()
   34. Array.prototype.unshift()
   35. Array.prototype.values()
   36. Array.prototype[@@iterator]()
   37. get Array[@@species]
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()