Array

由於本文件沒有此語言的翻譯版本,您閱讀的是英文版的內容。 幫助我們翻譯這篇文章!

JavaScript 中的 Array 全域物件被用於建構陣列;陣列為高階(high-level)、似列表(list-like)的物件。

建立陣列

var fruits = ['Apple', 'Banana'];

console.log(fruits.length);
// 2

(透過索引)取得陣列項目

var first = fruits[0];
// Apple

var last = fruits[fruits.length - 1];
// Banana

迭代陣列

fruits.forEach(function(item, index, array) {
  console.log(item, index);
});
// Apple 0
// Banana 1

加入項目至陣列末端

var newLength = fruits.push('Orange');
// ["Apple", "Banana", "Orange"]

移除陣列末端項目

var last = fruits.pop(); // 移除 (最末端的) Orange
// ["Apple", "Banana"];

移除陣列前端項目

var first = fruits.shift(); // 移除 (最前端的) Apple
// ["Banana"];

加入項目至陣列前端

var newLength = fruits.unshift('Strawberry') // 加到陣列前端
// ["Strawberry", "Banana"];

在陣列中尋找項目的索引

fruits.push('Mango');
// ["Strawberry", "Banana", "Mango"]

var pos = fruits.indexOf('Banana');
// 1

移除指定索引位置的項目

var removedItem = fruits.splice(pos, 1); // 移除 pos 起的 1 個項目
                                        
// ["Strawberry", "Mango"]

移除指定索引位置起的多個項目

var vegetables = ['Cabbage', 'Turnip', 'Radish', 'Carrot'];
console.log(vegetables); 
// ["Cabbage", "Turnip", "Radish", "Carrot"]

var pos = 1, n = 2;

var removedItems = vegetables.splice(pos, n); 
// 這就是移除項目的方式,
// n 表示從該位置 (pos) 開始,一直到陣列的尾端有多少項目需要移除

console.log(vegetables); 
// ["Cabbage", "Carrot"] (原始的陣列被改變)

console.log(removedItems); 
// ["Turnip", "Radish"]

複製陣列

var shallowCopy = fruits.slice(); // 這就是複製陣列的方式
// ["Strawberry", "Mango"]

語法

[element0, element1, ..., elementN]
new Array(element0, element1[, ...[, elementN]])
new Array(arrayLength)

參數

elementN
除了只傳遞一個參數給 Array 構造函數,且該參數為一個數字的情況(詳見下方的 arrayLength 參數),JavaScript 陣列會以傳入的元素進行初始化。
請注意,這種特殊情況僅適用於以 Array 構造函數建立的 JavaScript 陣列,而不適用於以括號語法建立的陣列常值(Array Literals)。
arrayLength
如果傳遞給 Array 構造函數的唯一參數是 0 和 232-1(含)之間的整數,將回傳一個新的 JavaScript 陣列,其長度被設定為這個數字。如果參數是任何其他數值,將拋出 RangeError 異常。

說明

Array(「陣列」)是類似列表(list)的物件(Object),它們的原型(Prototype)擁有方法(methods)來執行遍歷和變異操作。JavaScript 陣列的長度(元素數量),以及其元素的類型都不是固定的。取決於工程師如何選擇使用陣列,可以隨時更改陣列的長度,也可不連續儲存資料, 所以並不保證這些資料是集中的。一般情況下,這些特性很方便使用;但若這些功能都不符合您的用途,您可能會想使用型別陣列(typed arrays)。

有些人認為即便會發生警告,仍然不應該使用關聯陣列,而應該使用 objects。您可參考輕量級 JavaScript 字典當中的範例。

存取陣列元素

JavaScript 陣列是 zero-indexed:陣列元素的索引值編排從 0 開始,而最後一個元素的索引值等同於陣列的 length 屬性減 1。

var arr = ['this is the first element', 'this is the second element'];
console.log(arr[0]);              // 紀錄出 'this is the first element'
console.log(arr[1]);              // 記錄出 'this is the second element'
console.log(arr[arr.length - 1]); // 記錄出 'this is the second element'

Array 元素同時也是物件的屬性,與 toString 是一種屬性相同。但若要透過下面這種方式存取陣列元素,因為屬性名稱無效的關係,會發生語法錯誤:

console.log(arr.0); // 語法錯誤

會造成如此的原因沒有什麼特別的,在 JavaScript 當中無法用小數點的方式來參照一個名稱開頭為數字的屬性,而必須括號的表示方式來存取。舉例來說,若您有個物件的屬性名稱為「3d」,就只能用括號的方式來參照。

請看下列範例:

var years = [1950, 1960, 1970, 1980, 1990, 2000, 2010];
console.log(years.0);   // 語法錯誤
console.log(years[0]);  // 程式正常
renderer.3d.setTexture(model, 'character.png');     // 語法錯誤
renderer['3d'].setTexture(model, 'character.png');  // 程式正常

注意:以這個 '3d' 例子來說,必須用引號將 3d 包起來。您也可以將 JavaScript 陣列的索引用引號包起來(例如使用 years['2'] 而不用 years[2]),但這不是必要的。JavaScript 會透過隱含的 toString,將 years[2] 當中的 2 強制轉換為字串。由於這個原因,'2''02' 會參照到 years 物件中的不同項目,下列程式範例結果可能回傳 true

console.log(years['2'] != years['02']);

另一種類似的情況是,物件屬性剛好與保留字(!)相同的情況。這種情況下僅能透過括號表示方式當中的字串常值來存取:

var promise = {
  'var'  : 'text',
  'array': [1, 2, 3, 4]
};

console.log(promise['var']);

length 與數值屬性的關係

JavaScript 陣列的 length 屬性和其數值屬性相關。許多陣列的方法被呼叫時會參考 length 屬性的值(例如 joinsliceindexOf 等)。而有另一些方法則會去改變 length 屬性的值,如 pushsplice

var fruits = [];
fruits.push('banana', 'apple', 'peach');

console.log(fruits.length); // 3

如果給陣列設定一個數值屬性,其值為有效但超過當下範圍的陣列 index,JavaScript 引擎會依照此數值更新陣列的 length 屬性:

fruits[5] = 'mango';
console.log(fruits[5]); // 'mango'
console.log(Object.keys(fruits));  // ['0', '1', '2', '5']
console.log(fruits.length); // 6

提高 length 屬性。

fruits.length = 10;
console.log(Object.keys(fruits)); // ['0', '1', '2', '5']
console.log(fruits.length); // 10

降低 length 屬性則會刪除陣列元素。

fruits.length = 2;
console.log(Object.keys(fruits)); // ['0', '1']
console.log(fruits.length); // 2

Array.length 頁面裡有進一步解釋。

使用 match 回傳結果來建立陣列

在字串與正規表示式之間的比對結果會產生一個 javascript 陣列。此陣列內含關於比對資訊的屬性與元素。 這樣的陣列由RegExp.exec, String.match, 和 String.replace 所產生。參考以下範例和表格,會有助於說明這些屬性和元素:

// 比對一個字元 d,後面接著一或多個 b,再接著一個 d
// Remember matched b's and the following d
// 忽略大小寫

var myRe = /d(b+)(d)/i;
var myArray = myRe.exec('cdbBdbsbz');

這項比對結果的屬性與元素參考如下:

屬性/元素 說明 範例
input 唯讀屬性,代表 正規表示式用以比對的原始字串。 cdbBdbsbz
index 唯讀屬性,代表在字串中比對得到的索引,是以零為基礎(從0開始)。 1
[0] 一個唯獨元素以表示最後符合的字串 dbBd
[1], ...[n] Read-only elements that specify the parenthesized substring matches, if included in the regular expression. The number of possible parenthesized substrings is unlimited. [1]: bB
[2]: d

屬性

Array.length
Array 建構子的長度為 1。
get Array[@@species]
用來建立衍生物件的建構函數。
Array.prototype
可加入屬性至所有陣列物件。

方法

Array.from()
用類似陣列或可列舉物件,來建立新的 Array 實例。
Array.isArray()
若變數是陣列就回傳 true,否則回傳 false。
Array.of()
用可變數量的引數來建立新的 Array 實例,不論引數的數量或型別。

Array 實例

所有的陣列實例都繼承自 Array.prototype。若修改這個陣列建構子 (Array constructor) 的原型物件 (prototype object),將會影響所有的陣列實體。

屬性

方法

Mutator methods

Accessor methods

Iteration methods

Array 泛型方法

泛型陣列並非標準且已被棄用,將會在不久之後被去除。 

有時你想將陣列方法用於字串或其他類陣列物件(像是函數 arguments)。藉此操作,你將此字串視為由字元組成的陣列(反之為將其他非陣列視為物件)。如範例,若要確認字串中的每個字元是不是字母,你可能會這樣寫:

function isLetter(character) {
  return character >= 'a' && character <= 'z';
}

if (Array.prototype.every.call(str, isLetter)) {
  console.log("The string '" + str + "' contains only letters!");
}

這種表示法相當浪費,JavaScript 1.6 導入了一個通用方法:

if (Array.every(str, isLetter)) {
  console.log("The string '" + str + "' contains only letters!");
}

Generics 也同樣可用於 String.

並非 ECMAScript 的標準,且不被非 Gecko 引擎的瀏覽器支援。你應該將你的物件用  Array.from() 轉為陣列,以標準替代原有的方法;雖然此方法可能不被舊的瀏覽器所支援:

if (Array.from(str).every(isLetter)) { 
  console.log("The string '" + str + "' contains only letters!"); 
}

範例

範例:建立陣列

以下範例會產生長度為 0 的 msgArray 陣列,然後指派字串值到 msgArray[0]msgArray[99],使陣列的長度變為 100。

var msgArray = [];
msgArray[0] = 'Hello';
msgArray[99] = 'world';

if (msgArray.length === 100) {
  console.log('The length is 100.');
}

建立二維陣列

以下範例會用字串產生一張西洋棋盤的二維陣列。第一步是將士兵 'p' 從 (6,4) 移動至 (4,4),然後清空原本的位置 (6,4)。

var board = [ 
  ['R','N','B','Q','K','B','N','R'],
  ['P','P','P','P','P','P','P','P'],
  [' ',' ',' ',' ',' ',' ',' ',' '],
  [' ',' ',' ',' ',' ',' ',' ',' '],
  [' ',' ',' ',' ',' ',' ',' ',' '],
  [' ',' ',' ',' ',' ',' ',' ',' '],
  ['p','p','p','p','p','p','p','p'],
  ['r','n','b','q','k','b','n','r'] ];

console.log(board.join('\n') + '\n\n');

// 將士兵往前移兩步
board[4][4] = board[6][4];
board[6][4] = ' ';
console.log(board.join('\n'));

以下是輸出結果:

R,N,B,Q,K,B,N,R
P,P,P,P,P,P,P,P
 , , , , , , , 
 , , , , , , , 
 , , , , , , , 
 , , , , , , , 
p,p,p,p,p,p,p,p
r,n,b,q,k,b,n,r

R,N,B,Q,K,B,N,R
P,P,P,P,P,P,P,P
 , , , , , , , 
 , , , , , , , 
 , , , ,p, , , 
 , , , , , , , 
p,p,p,p, ,p,p,p
r,n,b,q,k,b,n,r

使用陣列來以表格顯示多個數值

values = [];
for (var x = 0; x < 10; x++){
 values.push([
  2 ** x,
  2 * x ** 2
 ])
};
console.table(values)

結果會是

0	1	0
1	2	2
2	4	8
3	8	18
4	16	32
5	32	50
6	64	72
7	128	98
8	256	128
9	512	162

(第一欄為索引)

規範

技術規格 狀態 備註
ECMAScript 1st Edition (ECMA-262) Standard 初次定義。
ECMAScript 5.1 (ECMA-262)
The definition of 'Array' in that specification.
Standard 加入新方法:Array.isArray, indexOf, lastIndexOf, every, some, forEach, map, filter, reduce, reduceRight
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Array' in that specification.
Standard 加入新方法:Array.from, Array.of, find, findIndex, fill, copyWithin
ECMAScript 2016 (ECMA-262)
The definition of 'Array' in that specification.
Standard 加入新方法:Array.prototype.includes()

瀏覽器相容性

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
ArrayChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
concatChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
copyWithinChrome Full support 45Edge Full support 12Firefox Full support 32IE No support NoOpera Full support 32Safari Full support 9WebView Android Full support YesChrome Android Full support 45Firefox Android Full support 32Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support 4.0.0
entriesChrome Full support 38Edge Full support 12Firefox Full support 28IE No support NoOpera Full support 25Safari Full support 8WebView Android Full support YesChrome Android Full support 38Firefox Android Full support 28Opera Android Full support YesSafari iOS Full support 8Samsung Internet Android Full support Yesnodejs Full support 0.12
everyChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
fillChrome Full support 45Edge Full support 12Firefox Full support 31IE No support NoOpera Full support YesSafari Full support 8WebView Android Full support YesChrome Android Full support 45Firefox Android Full support 31Opera Android Full support YesSafari iOS Full support 8Samsung Internet Android Full support Yesnodejs Full support 4.0.0
Full support 4.0.0
Full support 0.12
Disabled
Disabled From version 0.12: this feature is behind the --harmony runtime flag.
filterChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
findChrome Full support 45Edge Full support 12Firefox Full support 25IE No support NoOpera Full support 32Safari Full support 8WebView Android Full support YesChrome Android Full support 45Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support 8Samsung Internet Android Full support Yesnodejs Full support 4.0.0
Full support 4.0.0
Full support 0.12
Disabled
Disabled From version 0.12: this feature is behind the --harmony runtime flag.
findIndexChrome Full support 45Edge Full support 12Firefox Full support 25IE No support NoOpera Full support 32Safari Full support 8WebView Android Full support YesChrome Android Full support 45Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support 8Samsung Internet Android Full support Yesnodejs Full support 4.0.0
Full support 4.0.0
Full support 0.12
Disabled
Disabled From version 0.12: this feature is behind the --harmony runtime flag.
flatChrome Full support 69Edge No support NoFirefox Full support 62IE No support NoOpera Full support 56Safari Full support 12WebView Android Full support 69Chrome Android Full support 69Firefox Android Full support 62Opera Android Full support 48Safari iOS Full support 12Samsung Internet Android Full support 10.0nodejs Full support 11.0.0
flatMapChrome Full support 69Edge No support NoFirefox Full support 62IE No support NoOpera Full support 56Safari Full support 12WebView Android Full support 69Chrome Android Full support 69Firefox Android Full support 62Opera Android Full support 48Safari iOS Full support 12Samsung Internet Android Full support 10.0nodejs Full support 11.0.0
forEachChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
fromChrome Full support 45Edge Full support 12Firefox Full support 32IE No support NoOpera Full support YesSafari Full support 9WebView Android Full support 45Chrome Android Full support 45Firefox Android Full support 32Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support 4.0.0
includesChrome Full support 47Edge Full support 14Firefox Full support 43IE No support NoOpera Full support 34Safari Full support 9WebView Android Full support YesChrome Android Full support 47Firefox Android Full support 43Opera Android Full support 34Safari iOS Full support 9Samsung Internet Android Full support Yesnodejs Full support 6.0.0
Full support 6.0.0
Full support 5.0.0
Disabled
Disabled From version 5.0.0: this feature is behind the --harmony runtime flag.
indexOfChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
isArrayChrome Full support 5Edge Full support 12Firefox Full support 4IE Full support 9Opera Full support 10.5Safari Full support 5WebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
joinChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
keysChrome Full support 38Edge Full support 12Firefox Full support 28IE No support NoOpera Full support 25Safari Full support 8WebView Android Full support YesChrome Android Full support 38Firefox Android Full support 28Opera Android Full support YesSafari iOS Full support 8Samsung Internet Android Full support Yesnodejs Full support 0.12
lastIndexOfChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
lengthChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
mapChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
observe
DeprecatedNon-standard
Chrome No support 36 — 52Edge No support NoFirefox No support NoIE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoFirefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android No support Nonodejs No support No
ofChrome Full support 45Edge Full support 12Firefox Full support 25IE No support NoOpera Full support YesSafari Full support 9WebView Android Full support YesChrome Android Full support 39Firefox Android Full support 25Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 4.0nodejs Full support 4.0.0
popChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
prototypeChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
pushChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
reduceChrome Full support 3Edge Full support 12Firefox Full support 3IE Full support 9Opera Full support 10.5Safari Full support 4.1WebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support 4Samsung Internet Android Full support 1.0nodejs Full support Yes
reduceRightChrome Full support 3Edge Full support 12Firefox Full support 3IE Full support 9Opera Full support 10.5Safari Full support 4.1WebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support 4Samsung Internet Android Full support 1.0nodejs Full support Yes
reverseChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
shiftChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
sliceChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
someChrome Full support 1Edge Full support 12Firefox Full support 1.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
sortChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
spliceChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5
Notes
Full support 5.5
Notes
Notes From Internet Explorer 5.5 through 8, all elements of the array will not be deleted if deleteCount is omitted. This behavior was fixed in Internet Explorer 9.
Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
toLocaleStringChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
toSource
Non-standard
Chrome No support NoEdge No support NoFirefox Full support 1IE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoFirefox Android Full support 4Opera Android No support NoSafari iOS No support NoSamsung Internet Android No support Nonodejs No support No
toStringChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support ≤37Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes
unobserve
DeprecatedNon-standard
Chrome No support 36 — 52Edge No support NoFirefox No support NoIE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoFirefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android No support Nonodejs No support No
unshiftChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
valuesChrome Full support 66Edge Full support 12Firefox Full support 60IE No support NoOpera Full support 53Safari Full support 9WebView Android Full support 66Chrome Android Full support 66Firefox Android Full support 60Opera Android Full support 47Safari iOS Full support 9Samsung Internet Android Full support 9.0nodejs Full support 10.9.0
Full support 10.9.0
Full support 6.5.0
Notes Disabled
Notes The --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.
No support 0.12 — 4.0.0
@@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 38Firefox 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
@@speciesChrome Full support 51Edge No support NoFirefox Full support 48IE No support NoOpera Full support 38Safari ? WebView Android Full support 51Chrome Android Full support 51Firefox Android Full support 48Opera Android Full support 41Safari iOS ? Samsung Internet Android Full support 5.0nodejs Full support 6.5.0
Full support 6.5.0
Full support 6.0.0
Disabled
Disabled From version 6.0.0: this feature is behind the --harmony runtime flag.
@@unscopablesChrome Full support 38Edge Full support 12Firefox Full support 48IE No support NoOpera Full support 25Safari ? WebView Android Full support 38Chrome Android Full support 38Firefox Android Full support 48Opera Android Full support 25Safari iOS ? Samsung Internet Android Full support 3.0nodejs Full support 0.12

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.
Deprecated. Not for use in new websites.
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.
Uses a non-standard name.
Uses a non-standard name.

參見