mirror of
https://github.com/fofolee/uTools-Manuals.git
synced 2025-06-09 23:44:06 +08:00
408 lines
35 KiB
HTML
408 lines
35 KiB
HTML
<article id="wikiArticle">
|
||
<div>
|
||
<div>
|
||
<div></div>
|
||
</div>
|
||
</div>
|
||
<p><strong><code>arguments</code></strong> 是一个对应于传递给函数的参数的类数组对象。</p>
|
||
<h2 id="语法">语法</h2>
|
||
<pre><code class="language-javascript">arguments</code></pre>
|
||
<h2 id="Description" name="Description">描述</h2>
|
||
<p><code>arguments</code>对象是所有（非箭头）函数中都可用的<strong>局部变量</strong>。你可以使用<code>arguments</code>对象在函数中引用函数的参数。此对象包含传递给函数的每个参数，第一个参数在索引0处。例如，如果一个函数传递了三个参数，你可以以如下方式引用他们：</p>
|
||
<pre><code class="language-javascript">arguments[0]
|
||
arguments[1]
|
||
arguments[2]
|
||
</code></pre>
|
||
<p>参数也可以被设置：</p>
|
||
<pre><code class="language-javascript">arguments[1] = 'new value';</code></pre>
|
||
<p><code>arguments</code>对象不是一个 <a href="Reference/Array" title="REDIRECT Array"><code>Array</code></a> 。它类似于<code>Array</code>，但除了length属性和索引元素之外没有任何<code>Array</code>属性。例如，它没有 <a href="Reference/Global_Objects/Array/pop" title="JavaScript/Reference/Global_Objects/Array/pop">pop</a> 方法。但是它可以被转换为一个真正的<code>Array</code>：</p>
|
||
<pre><code class="language-javascript">var args = Array.prototype.slice.call(arguments);
|
||
var args = [].slice.call(arguments);
|
||
|
||
// ES2015
|
||
const args = Array.from(arguments);
|
||
const args = [...arguments];
|
||
</code></pre>
|
||
<div class="warning">
|
||
<p>对参数使用slice会阻止某些JavaScript引擎中的优化 (比如 V8 - <a class="external" href="https://github.com/petkaantonov/bluebird/wiki/Optimization-killers#3-managing-arguments" rel="noopener">更多信息</a>)。如果你关心性能，尝试通过遍历arguments对象来构造一个新的数组。另一种方法是使用被忽视的<code>Array</code>构造函数作为一个函数：</p>
|
||
<pre><code class="language-javascript">var args = (arguments.length === 1 ? [arguments[0]] : Array.apply(null, arguments));
|
||
</code></pre>
|
||
</div>
|
||
<p>如果调用的参数多于正式声明接受的参数，则可以使用<code>arguments</code>对象。这种技术对于可以传递可变数量的参数的函数很有用。使用 <code><a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Functions_and_function_scope/arguments/length">arguments.length</a></code>来确定传递给函数参数的个数，然后使用<code>arguments</code>对象来处理每个参数。要确定函数<a href="/zh-CN/docs/Glossary/Signature/Function">签名</a>中（输入）参数的数量，请使用<code><a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Function/length">Function.length</a></code>属性。</p>
|
||
<h3 id="对参数使用_typeof">对参数使用 <code>typeof</code></h3>
|
||
<p>typeof参数返回 'object'。</p>
|
||
<pre><code class="language-javascript">console.log(typeof arguments); // 'undefined'
|
||
// arguments 对象只能在函数内使用
|
||
function test(a){
|
||
console.log(a,Object.prototype.toString.call(arguments));
|
||
console.log(arguments[0],arguments[1]);
|
||
console.log(typeof arguments[0]);
|
||
}
|
||
test(1);
|
||
/*
|
||
1 "[object Arguments]"
|
||
1 undefined
|
||
number
|
||
*/</code></pre>
|
||
<p>可以使用索引确定单个参数的类型。</p>
|
||
<pre><code class="language-javascript">console.log(typeof arguments[0]); //this will return the typeof individual arguments.</code></pre>
|
||
<h3 id="对参数使用扩展语法">对参数使用扩展语法</h3>
|
||
<p>您还可以使用<a href="Reference/Global_Objects/Array/from" title="Array.from() 方法从一个类似数组或可迭代对象中创建一个新的数组实例。"><code>Array.from()</code></a>方法或<a href="Reference/Operators/Spread_operator">扩展运算符</a>将参数转换为真实数组：</p>
|
||
<pre><code class="language-javascript">var args = Array.from(arguments);
|
||
var args = [...arguments];</code></pre>
|
||
<h2 id="Properties" name="Properties">属性</h2>
|
||
<dl>
|
||
<dt><code><a href="Reference/Functions/arguments/callee" title="JavaScript/Reference/Functions_and_function_scope/arguments/callee">arguments.callee</a></code></dt>
|
||
<dd>指向当前执行的函数。</dd>
|
||
<dt><code><a href="Reference/Functions/arguments/caller" title="JavaScript/Reference/Functions_and_function_scope/arguments/caller">arguments.caller</a></code> <span class="icon-only-inline" title="This is an obsolete API and is no longer guaranteed to work."><i class="icon-trash"> </i></span></dt>
|
||
<dd>指向调用当前函数的函数。</dd>
|
||
<dt><code><a href="Reference/Functions/arguments/length" title="JavaScript/Reference/Functions_and_function_scope/arguments/length">arguments.length</a></code></dt>
|
||
<dd>指向传递给当前函数的参数数量。</dd>
|
||
<dt><code><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/arguments/@@iterator">arguments[@@iterator]</a></code></dt>
|
||
<dd>返回一个新的Array迭代器对象，该对象包含参数中每个索引的值。</dd>
|
||
<dt>注意:现在在严格模式下，<code>arguments</code>对象已与过往不同。<code><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/arguments/@@iterator">arguments[@@iterator]</a></code>不再与函数的实际形参之间共享，同时caller属性也被移除。</dt>
|
||
</dl>
|
||
<h2 id="Examples" name="Examples">例子</h2>
|
||
<h3 id="遍历参数求和">遍历参数求和</h3>
|
||
<pre><code class="language-javascript">function add() {
|
||
var sum =0,
|
||
len = arguments.length;
|
||
for(var i=0; i<len; i++){
|
||
sum += arguments[i];
|
||
}
|
||
return sum;
|
||
}
|
||
add() // 0
|
||
add(1) // 1
|
||
add(1,2,3,4); // 10</code></pre>
|
||
<h3 id="Example:_Defining_function_that_concatenates_several_strings" name="Example:_Defining_function_that_concatenates_several_strings">定义连接字符串的函数</h3>
|
||
<p>这个例子定义了一个函数来连接字符串。这个函数唯一正式声明了的参数是一个字符串，该参数指定一个字符作为衔接点来连接字符串。该函数定义如下：</p>
|
||
<pre><code class="language-js">function myConcat(separator) {
|
||
var args = Array.prototype.slice.call(arguments, 1);
|
||
return args.join(separator);
|
||
}</code></pre>
|
||
<p>你可以传递任意数量的参数到该函数，并使用每个参数作为列表中的项创建列表。</p>
|
||
<pre><code class="language-js">// returns "red, orange, blue"
|
||
myConcat(", ", "red", "orange", "blue");
|
||
|
||
// returns "elephant; giraffe; lion; cheetah"
|
||
myConcat("; ", "elephant", "giraffe", "lion", "cheetah");
|
||
|
||
// returns "sage. basil. oregano. pepper. parsley"
|
||
myConcat(". ", "sage", "basil", "oregano", "pepper", "parsley");</code></pre>
|
||
<h3 id="Example:_Defining_a_function_that_creates_HTML_lists" name="Example:_Defining_a_function_that_creates_HTML_lists">定义创建HTML列表的方法</h3>
|
||
<p>这个例子定义了一个函数通过一个字符串来创建HTML列表。这个函数唯一正式声明了的参数是一个字符。当该参数为 "<code>u</code>" 时，创建一个无序列表 (项目列表)；当该参数为 "<code>o</code>" 时，则创建一个有序列表 (编号列表)。该函数定义如下：</p>
|
||
<pre><code class="language-js language-js" style="padding: 1em 0px 1em 30px; font-size: 14px; white-space: normal;"><code class="language-js" style="direction: ltr; white-space: pre;"><span class="keyword token" style="color: #0077aa;">function</span> <span class="function token" style="color: #dd4a68;">list<span class="punctuation token" style="color: #999999;">(</span></span>type<span class="punctuation token" style="color: #999999;">)</span> <span class="punctuation token" style="color: #999999;">{</span>
|
||
<span class="keyword token" style="color: #0077aa;">var</span> result <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">=</span> <span class="string token" style="color: #669900;">"<"</span> <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">+</span> type <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">+</span> <span class="string token" style="color: #669900;">"l><li>"</span><span class="punctuation token" style="color: #999999;">;</span>
|
||
<span class="keyword token" style="color: #0077aa;">var</span> args <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">=</span> Array<span class="punctuation token" style="color: #999999;">.</span>prototype<span class="punctuation token" style="color: #999999;">.</span>slice<span class="punctuation token" style="color: #999999;">.</span><span class="function token" style="color: #dd4a68;">call<span class="punctuation token" style="color: #999999;">(</span></span>arguments<span class="punctuation token" style="color: #999999;">,</span> <span class="number token" style="color: #990055;">1</span><span class="punctuation token" style="color: #999999;">)</span><span class="punctuation token" style="color: #999999;">;</span>
|
||
result <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">+</span><span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">=</span> args<span class="punctuation token" style="color: #999999;">.</span><span class="function token" style="color: #dd4a68;">join<span class="punctuation token" style="color: #999999;">(</span></span><span class="string token" style="color: #669900;">"</li><li>"</span><span class="punctuation token" style="color: #999999;">)</span><span class="punctuation token" style="color: #999999;">;</span>
|
||
result <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">+</span><span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">=</span> <span class="string token" style="color: #669900;">"</li></"</span> <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">+</span> type <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">+</span> <span class="string token" style="color: #669900;">"l>"</span><span class="punctuation token" style="color: #999999;">;</span><span class="comment token" style="color: #708090;"> // end list
|
||
</span>
|
||
<span class="keyword token" style="color: #0077aa;">return</span> result<span class="punctuation token" style="color: #999999;">;</span>
|
||
<span class="punctuation token" style="color: #999999;">}</span></code></code></pre>
|
||
<p>你可以传递任意数量的参数到该函数，并将每个参数作为一个项添加到指定类型的列表中。例如：</p>
|
||
<pre><code class="language-js language-js" style="padding: 1em 0px 1em 30px; font-size: 14px; white-space: normal;"><code class="language-js" style="direction: ltr; white-space: pre;"><span class="keyword token" style="color: #0077aa;">var</span> listHTML <span class="operator token" style="background: rgba(255, 255, 255, 0.498039); color: #a67f59;">=</span> <span class="function token" style="color: #dd4a68;">list<span class="punctuation token" style="color: #999999;">(</span></span><span class="string token" style="color: #669900;">"u"</span><span class="punctuation token" style="color: #999999;">,</span> <span class="string token" style="color: #669900;">"One"</span><span class="punctuation token" style="color: #999999;">,</span> <span class="string token" style="color: #669900;">"Two"</span><span class="punctuation token" style="color: #999999;">,</span> <span class="string token" style="color: #669900;">"Three"</span><span class="punctuation token" style="color: #999999;">)</span><span class="punctuation token" style="color: #999999;">;</span>
|
||
|
||
<span class="comment token" style="color: #708090;">/* listHTML is:
|
||
|
||
"<ul><li>One</li><li>Two</li><li>Three</li></ul>"
|
||
|
||
*/</span></code>
|
||
</code></pre>
|
||
<h3 id="剩余参数、默认参数和解构赋值参数">剩余参数、默认参数和解构赋值参数</h3>
|
||
<p><code>arguments</code>对象可以与<a href="Reference/Functions/Rest_parameters">剩余参数</a>、<a href="Reference/Functions/Default_parameters">默认参数</a>和<a href="Reference/Operators/Destructuring_assignment">解构赋值</a>参数结合使用。</p>
|
||
<pre><code class="language-javascript">function foo(...args) {
|
||
return args;
|
||
}
|
||
foo(1, 2, 3); // [1,2,3]
|
||
</code></pre>
|
||
<p>在严格模式下，<a href="Reference/Functions/Rest_parameters">剩余参数</a>、<a href="Reference/Functions/Default_parameters">默认参数</a>和<a href="Reference/Operators/Destructuring_assignment">解构赋值</a>参数的存在不会改变 <code>arguments</code>对象的行为，但是在非严格模式下就有所不同了。</p>
|
||
<p>当非严格模式中的函数<strong>没有</strong>包含<a href="Reference/Functions/Rest_parameters">剩余参数</a>、<a href="Reference/Functions/Default_parameters">默认参数</a>和<a href="Reference/Operators/Destructuring_assignment">解构赋值</a>，那么<code>arguments</code>对象中的值<strong>会</strong>跟踪参数的值（反之亦然）。看下面的代码：</p>
|
||
<pre><code class="language-javascript">function func(a) {
|
||
arguments[0] = 99; // 更新了arguments[0] 同样更新了a
|
||
console.log(a);
|
||
}
|
||
func(10); // 99
|
||
</code></pre>
|
||
<p>并且</p>
|
||
<pre><code class="language-javascript">function func(a) {
|
||
a = 99; // 更新了a 同样更新了arguments[0]
|
||
console.log(arguments[0]);
|
||
}
|
||
func(10); // 99
|
||
</code></pre>
|
||
<p>当非严格模式中的函数<strong>有</strong>包含<a href="Reference/Functions/Rest_parameters">剩余参数</a>、<a href="Reference/Functions/Default_parameters">默认参数</a>和<a href="Reference/Operators/Destructuring_assignment">解构赋值</a>，那么<code>arguments</code>对象中的值<strong>不会</strong>跟踪参数的值（反之亦然）。相反, <code>arguments</code>反映了调用时提供的参数：</p>
|
||
<pre><code class="language-javascript">function func(a = 55) {
|
||
arguments[0] = 99; // updating arguments[0] does not also update a
|
||
console.log(a);
|
||
}
|
||
func(10); // 10</code></pre>
|
||
<p>并且</p>
|
||
<pre><code class="language-javascript">function func(a = 55) {
|
||
a = 99; // updating a does not also update arguments[0]
|
||
console.log(arguments[0]);
|
||
}
|
||
func(10); // 10</code></pre>
|
||
<p>并且</p>
|
||
<pre><code class="language-javascript">function func(a = 55) {
|
||
console.log(arguments[0]);
|
||
}
|
||
func(); // undefined
|
||
</code></pre>
|
||
<h2 id="规范">规范</h2>
|
||
<table class="standard-table">
|
||
<tbody>
|
||
<tr>
|
||
<th scope="col">Specification</th>
|
||
<th scope="col">Status</th>
|
||
<th scope="col">Comment</th>
|
||
</tr>
|
||
<tr>
|
||
<td><a class="external" href="https://www.ecma-international.org/publications/files/ECMA-ST-ARCH/ECMA-262,%201st%20edition,%20June%201997.pdf" hreflang="en" lang="en" rel="noopener" title="ECMAScript 1st Edition (ECMA-262)">ECMAScript 1st Edition (ECMA-262)</a></td>
|
||
<td><span class="spec-Standard">Standard</span></td>
|
||
<td>Initial definition. Implemented in JavaScript 1.1</td>
|
||
</tr>
|
||
<tr>
|
||
<td><a class="external" href="https://www.ecma-international.org/ecma-262/5.1/#sec-10.6" hreflang="en" lang="en" rel="noopener">ECMAScript 5.1 (ECMA-262)<br/><small lang="zh-CN">Arguments Object</small></a></td>
|
||
<td><span class="spec-Standard">Standard</span></td>
|
||
<td> </td>
|
||
</tr>
|
||
<tr>
|
||
<td><a class="external" href="https://www.ecma-international.org/ecma-262/6.0/#sec-arguments-exotic-objects" hreflang="en" lang="en" rel="noopener">ECMAScript 2015 (6th Edition, ECMA-262)<br/><small lang="zh-CN">Arguments Exotic Objects</small></a></td>
|
||
<td><span class="spec-Standard">Standard</span></td>
|
||
<td> </td>
|
||
</tr>
|
||
<tr>
|
||
<td><a class="external" href="https://tc39.github.io/ecma262/#sec-arguments-exotic-objects" hreflang="en" lang="en" rel="noopener">ECMAScript Latest Draft (ECMA-262)<br/><small lang="zh-CN">Arguments Exotic Objects</small></a></td>
|
||
<td><span class="spec-Draft">Draft</span></td>
|
||
<td> </td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<h2 id="浏览器兼容">浏览器兼容</h2>
|
||
<div class="hidden">The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out <a class="external" href="https://github.com/mdn/browser-compat-data" rel="noopener">https://github.com/mdn/browser-compat-data</a> and send us a pull request.</div>
|
||
<p></p><div class="bc-data"><a class="bc-github-link external" href="https://github.com/mdn/browser-compat-data" rel="noopener">Update compatibility data on GitHub</a><table class="bc-table bc-table-js"><thead><tr class="bc-platforms"><td></td><th class="bc-platform-desktop" colspan="6"><span>Desktop</span></th><th class="bc-platform-mobile" colspan="7"><span>Mobile</span></th><th class="bc-platform-server" colspan="1"><span>Server</span></th></tr><tr class="bc-browsers"><td></td><th class="bc-browser-chrome"><span class="bc-head-txt-label bc-head-icon-chrome">Chrome</span></th><th class="bc-browser-edge"><span class="bc-head-txt-label bc-head-icon-edge">Edge</span></th><th class="bc-browser-firefox"><span class="bc-head-txt-label bc-head-icon-firefox">Firefox</span></th><th class="bc-browser-ie"><span class="bc-head-txt-label bc-head-icon-ie">Internet Explorer</span></th><th class="bc-browser-opera"><span class="bc-head-txt-label bc-head-icon-opera">Opera</span></th><th class="bc-browser-safari"><span class="bc-head-txt-label bc-head-icon-safari">Safari</span></th><th class="bc-browser-webview_android"><span class="bc-head-txt-label bc-head-icon-webview_android">Android webview</span></th><th class="bc-browser-chrome_android"><span class="bc-head-txt-label bc-head-icon-chrome_android">Chrome for Android</span></th><th class="bc-browser-edge_mobile"><span class="bc-head-txt-label bc-head-icon-edge_mobile">Edge Mobile</span></th><th class="bc-browser-firefox_android"><span class="bc-head-txt-label bc-head-icon-firefox_android">Firefox for Android</span></th><th class="bc-browser-opera_android"><span class="bc-head-txt-label bc-head-icon-opera_android">Opera for Android</span></th><th class="bc-browser-safari_ios"><span class="bc-head-txt-label bc-head-icon-safari_ios">Safari on iOS</span></th><th class="bc-browser-samsunginternet_android"><span class="bc-head-txt-label bc-head-icon-samsunginternet_android">Samsung Internet</span></th><th class="bc-browser-nodejs"><span class="bc-head-txt-label bc-head-icon-nodejs">Node.js</span></th></tr></thead><tbody><tr><th scope="row"><code>arguments</code></th><td class="bc-supports-yes bc-browser-chrome"><span class="bc-browser-name">Chrome</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-edge"><span class="bc-browser-name">Edge</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-firefox"><span class="bc-browser-name">Firefox</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
1</td><td class="bc-supports-yes bc-browser-ie"><span class="bc-browser-name">IE</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-opera"><span class="bc-browser-name">Opera</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari"><span class="bc-browser-name">Safari</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-webview_android"><span class="bc-browser-name">WebView Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-chrome_android"><span class="bc-browser-name">Chrome Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-edge_mobile"><span class="bc-browser-name">Edge Mobile</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-firefox_android"><span class="bc-browser-name">Firefox Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
4</td><td class="bc-supports-yes bc-browser-opera_android"><span class="bc-browser-name">Opera Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari_ios"><span class="bc-browser-name">Safari iOS</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-samsunginternet_android"><span class="bc-browser-name">Samsung Internet Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-nodejs"><span class="bc-browser-name">nodejs</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td></tr><tr><th scope="row"><a href="Reference/Functions/arguments/callee"><code>callee</code></a></th><td class="bc-supports-yes bc-browser-chrome"><span class="bc-browser-name">Chrome</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-edge"><span class="bc-browser-name">Edge</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-firefox"><span class="bc-browser-name">Firefox</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
1</td><td class="bc-supports-yes bc-browser-ie"><span class="bc-browser-name">IE</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
6</td><td class="bc-supports-yes bc-browser-opera"><span class="bc-browser-name">Opera</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari"><span class="bc-browser-name">Safari</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-webview_android"><span class="bc-browser-name">WebView Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-chrome_android"><span class="bc-browser-name">Chrome Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-edge_mobile"><span class="bc-browser-name">Edge Mobile</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-firefox_android"><span class="bc-browser-name">Firefox Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
4</td><td class="bc-supports-yes bc-browser-opera_android"><span class="bc-browser-name">Opera Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari_ios"><span class="bc-browser-name">Safari iOS</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-samsunginternet_android"><span class="bc-browser-name">Samsung Internet Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-nodejs"><span class="bc-browser-name">nodejs</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td></tr><tr><th scope="row"><a href="Reference/Functions/arguments/caller"><code>caller</code></a> <div class="bc-icons"><abbr class="only-icon" title="Deprecated. Not for use in new websites."><span>Deprecated</span><i class="ic-deprecated"></i></abbr><abbr class="only-icon" title="Non-standard. Expect poor cross-browser support."><span>Non-standard</span><i class="ic-non-standard"></i></abbr></div></th><td class="bc-supports-no bc-browser-chrome"><span class="bc-browser-name">Chrome</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-edge"><span class="bc-browser-name">Edge</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-firefox"><span class="bc-browser-name">Firefox</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-ie"><span class="bc-browser-name">IE</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>? — 9</td><td class="bc-supports-no bc-browser-opera"><span class="bc-browser-name">Opera</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-safari"><span class="bc-browser-name">Safari</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-webview_android"><span class="bc-browser-name">WebView Android</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-chrome_android"><span class="bc-browser-name">Chrome Android</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-edge_mobile"><span class="bc-browser-name">Edge Mobile</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-firefox_android"><span class="bc-browser-name">Firefox Android</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-opera_android"><span class="bc-browser-name">Opera Android</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-safari_ios"><span class="bc-browser-name">Safari iOS</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-samsunginternet_android"><span class="bc-browser-name">Samsung Internet Android</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-no bc-browser-nodejs"><span class="bc-browser-name">nodejs</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td></tr><tr><th scope="row"><a href="Reference/Functions/arguments/length"><code>length</code></a></th><td class="bc-supports-yes bc-browser-chrome"><span class="bc-browser-name">Chrome</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-edge"><span class="bc-browser-name">Edge</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-firefox"><span class="bc-browser-name">Firefox</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
1</td><td class="bc-supports-yes bc-browser-ie"><span class="bc-browser-name">IE</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-opera"><span class="bc-browser-name">Opera</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari"><span class="bc-browser-name">Safari</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-webview_android"><span class="bc-browser-name">WebView Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-chrome_android"><span class="bc-browser-name">Chrome Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-edge_mobile"><span class="bc-browser-name">Edge Mobile</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-firefox_android"><span class="bc-browser-name">Firefox Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
4</td><td class="bc-supports-yes bc-browser-opera_android"><span class="bc-browser-name">Opera Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari_ios"><span class="bc-browser-name">Safari iOS</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-samsunginternet_android"><span class="bc-browser-name">Samsung Internet Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-nodejs"><span class="bc-browser-name">nodejs</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td></tr><tr><th scope="row"><a href="Reference/Functions/arguments/@@iterator"><code>@@iterator</code></a></th><td class="bc-supports-yes bc-browser-chrome"><span class="bc-browser-name">Chrome</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
52</td><td class="bc-supports-unknown bc-browser-edge"><span class="bc-browser-name">Edge</span><abbr title="Compatibility unknown; please update this.">
|
||
?
|
||
</abbr></td><td class="bc-supports-yes bc-browser-firefox"><span class="bc-browser-name">Firefox</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
46</td><td class="bc-supports-no bc-browser-ie"><span class="bc-browser-name">IE</span><abbr class="bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
</abbr>
|
||
No</td><td class="bc-supports-yes bc-browser-opera"><span class="bc-browser-name">Opera</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari"><span class="bc-browser-name">Safari</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
9</td><td class="bc-supports-yes bc-browser-webview_android"><span class="bc-browser-name">WebView Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
52</td><td class="bc-supports-yes bc-browser-chrome_android"><span class="bc-browser-name">Chrome Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
52</td><td class="bc-supports-unknown bc-browser-edge_mobile"><span class="bc-browser-name">Edge Mobile</span><abbr title="Compatibility unknown; please update this.">
|
||
?
|
||
</abbr></td><td class="bc-supports-yes bc-browser-firefox_android"><span class="bc-browser-name">Firefox Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
46</td><td class="bc-supports-yes bc-browser-opera_android"><span class="bc-browser-name">Opera Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td><td class="bc-supports-yes bc-browser-safari_ios"><span class="bc-browser-name">Safari iOS</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
9</td><td class="bc-supports-yes bc-browser-samsunginternet_android"><span class="bc-browser-name">Samsung Internet Android</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
6.0</td><td class="bc-supports-yes bc-browser-nodejs"><span class="bc-browser-name">nodejs</span><abbr class="bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
</abbr>
|
||
Yes</td></tr></tbody></table><section class="bc-legend" id="sect1"><h3 class="offscreen" id="Legend">Legend</h3><dl><dt><span class="bc-supports-yes bc-supports">
|
||
<abbr class="bc-level bc-level-yes only-icon" title="Full support">
|
||
<span>Full support</span>
|
||
|
||
</abbr></span></dt><dd>Full support</dd><dt><span class="bc-supports-no bc-supports">
|
||
<abbr class="bc-level bc-level-no only-icon" title="No support">
|
||
<span>No support</span>
|
||
|
||
</abbr></span></dt><dd>No support</dd><dt><span class="bc-supports-unknown bc-supports">
|
||
<abbr class="bc-level bc-level-unknown only-icon" title="Compatibility unknown">
|
||
<span>Compatibility unknown</span>
|
||
|
||
</abbr></span></dt><dd>Compatibility unknown</dd><dt><abbr class="only-icon" title="Non-standard. Expect poor cross-browser support."><span>Non-standard. Expect poor cross-browser support.</span><i class="ic-non-standard"></i></abbr></dt><dd>Non-standard. Expect poor cross-browser support.</dd><dt><abbr class="only-icon" title="Deprecated. Not for use in new websites."><span>Deprecated. Not for use in new websites.</span><i class="ic-deprecated"></i></abbr></dt><dd>Deprecated. Not for use in new websites.</dd></dl></section></div><p></p>
|
||
<h2 id="See_also" name="See_also">相关链接</h2>
|
||
<ul>
|
||
<li><a href="Reference/Function" title="此页面仍未被本地化, 期待您的翻译!"><code>Function</code></a></li>
|
||
</ul>
|
||
</article> |