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<article id="wikiArticle">
<div></div>
<p><strong><code>Object.getOwnPropertyNames()</code></strong>方法返回一个由指定对象的所有自身属性的属性名包括不可枚举属性但不包括Symbol值作为名称的属性组成的数组。</p>
<h2 id="Syntax" name="Syntax">语法</h2>
<pre><code class="language-javascript">Object.getOwnPropertyNames(<em>obj</em>)</code></pre>
<h3 id="参数">参数</h3>
<dl>
<dt><code>obj</code></dt>
<dd>一个对象,其自身的可枚举和不可枚举属性的名称被返回。</dd>
</dl>
<h3 id="返回值">返回值</h3>
<p>在给定对象上找到的自身属性对应的字符串数组。</p>
<h2 id="Description" name="Description" style="margin-bottom: 20px; line-height: 30px;">描述</h2>
<p><code>Object.getOwnPropertyNames()</code> 返回一个数组,该数组对元素是 <code>obj</code>自身拥有的枚举或不可枚举属性名称字符串。 数组中枚举属性的顺序与通过 <a href="Reference/Statements/for...in" title="for...in语句以任意顺序遍历一个对象的可枚举属性。对于每个不同的属性语句都会被执行。"><code>for...in</code></a> 循环(或 <a href="Reference/Global_Objects/Object/keys" title="Object.keys() 方法会返回一个由一个给定对象的自身可枚举属性组成的数组,数组中属性名的排列顺序和使用 for...in 循环遍历该对象时返回的顺序一致 。"><code>Object.keys</code></a>)迭代该对象属性时一致。数组中不可枚举属性的顺序未定义。</p>
<h2 id="示例">示例</h2>
<h3 id="使用_Object.getOwnPropertyNames()">使用 <code>Object.getOwnPropertyNames()</code></h3>
<pre><code class="language-javascript">var arr = ["a", "b", "c"];
console.log(Object.getOwnPropertyNames(arr).sort()); // ["0", "1", "2", "length"]
// 类数组对象
var obj = { 0: "a", 1: "b", 2: "c"};
console.log(Object.getOwnPropertyNames(obj).sort()); // ["0", "1", "2"]
// 使用Array.forEach输出属性名和属性值
Object.getOwnPropertyNames(obj).forEach(function(val, idx, array) {
console.log(val + " -&gt; " + obj[val]);
});
// 输出
// 0 -&gt; a
// 1 -&gt; b
// 2 -&gt; c
//不可枚举属性
var my_obj = Object.create({}, {
getFoo: {
value: function() { return this.foo; },
enumerable: false
}
});
my_obj.foo = 1;
console.log(Object.getOwnPropertyNames(my_obj).sort()); // ["foo", "getFoo"]
</code></pre>
<p>如果你只要获取到可枚举属性,查看<a href="Reference/Global_Objects/Object/keys" title="Object.keys() 方法会返回一个由一个给定对象的自身可枚举属性组成的数组,数组中属性名的排列顺序和使用 for...in 循环遍历该对象时返回的顺序一致 。"><code>Object.keys</code></a>或用<a href="Reference/Statements/for...in" title="for...in语句以任意顺序遍历一个对象的可枚举属性。对于每个不同的属性语句都会被执行。"><code>for...in</code></a>循环(还会获取到原型链上的可枚举属性,不过可以使用<a href="Reference/Global_Objects/Object/hasOwnProperty" title="hasOwnProperty() 方法会返回一个布尔值,指示对象自身属性中是否具有指定的属性"><code>hasOwnProperty()</code></a>方法过滤掉)。</p>
<p>下面的例子演示了该方法不会获取到原型链上的属性:</p>
<pre><code class="language-javascript">function ParentClass() {}
ParentClass.prototype.inheritedMethod = function() {};
function ChildClass() {
  this.prop = 5;
  this.method = function() {};
}
ChildClass.prototype = new ParentClass;
ChildClass.prototype.prototypeMethod = function() {};
console.log(
  Object.getOwnPropertyNames(
  new ChildClass() // ["prop", "method"]
  )
);
</code></pre>
<h3 id="只获取不可枚举的属性">只获取不可枚举的属性</h3>
<p>下面的例子使用了 <a href="Reference/Global_Objects/Array/filter" title="filter() 方法创建一个新数组, 其包含通过所提供函数实现的测试的所有元素。"><code>Array.prototype.filter()</code></a> 方法,从所有的属性名数组(使用<code>Object.getOwnPropertyNames()</code>方法获得)中去除可枚举的属性(使用<a href="Reference/Global_Objects/Object/keys" title="Object.keys() 方法会返回一个由一个给定对象的自身可枚举属性组成的数组,数组中属性名的排列顺序和使用 for...in 循环遍历该对象时返回的顺序一致 。"><code>Object.keys()</code></a>方法获得),剩余的属性便是不可枚举的属性了:</p>
<pre><code class="language-javascript">var target = myObject;
var enum_and_nonenum = Object.getOwnPropertyNames(target);
var enum_only = Object.keys(target);
var nonenum_only = enum_and_nonenum.filter(function(key) {
    var indexInEnum = enum_only.indexOf(key);
    if (indexInEnum == -1) {
        // 没有发现在enum_only健集中意味着这个健是不可枚举的,
        // 因此返回true 以便让它保持在过滤结果中
        return true;
    } else {
        return false;
    }
});
console.log(nonenum_only);</code></pre>
<pre>注:<a href="https://developer.mozilla.orgReference/Global_Objects/Array/filter">Array.filter(filt_func)方法</a>创建一个新数组, 其包含通过所提供函数实现的测试的所有元素。</code></pre>
<h2 id="Notes" name="Notes">提示</h2>
<p>在 ES5 中,如果参数不是一个原始对象类型,将抛出一个 <a href="Reference/Global_Objects/TypeError" title="TypeError类型错误 对象用来表示值的类型非预期类型时发生的错误。"><code>TypeError</code></a>  异常。在 ES2015 非对象参数被强制转换为对象 <strong></strong></p>
<pre><code class="language-javascript">Object.getOwnPropertyNames('foo');
// TypeError: "foo" is not an object (ES5 code)
Object.getOwnPropertyNames('foo');
// ['length', '0', '1', '2'] (ES2015 code)
</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/ecma-262/5.1/#sec-15.2.3.4" hreflang="en" lang="en" rel="noopener">ECMAScript 5.1 (ECMA-262)<br/><small lang="zh-CN">Object.getOwnPropertyNames</small></a></td>
<td><span class="spec-Standard">Standard</span></td>
<td>Initial definition. Implemented in JavaScript 1.8.5.</td>
</tr>
<tr>
<td><a class="external" href="https://www.ecma-international.org/ecma-262/6.0/#sec-object.getownpropertynames" hreflang="en" lang="en" rel="noopener">ECMAScript 2015 (6th Edition, ECMA-262)<br/><small lang="zh-CN">Object.getOwnPropertyNames</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-object.getownpropertynames" hreflang="en" lang="en" rel="noopener">ECMAScript Latest Draft (ECMA-262)<br/><small lang="zh-CN">Object.getOwnPropertyNames</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>getOwnPropertyNames</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>
5</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>
12</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>
4</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>
9</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>
12</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>
5</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></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></dl></section></div><p></p>
<h2 id="Firefox-specific_notes">Firefox-specific notes</h2>
<p>Firefox 28 (Firefox 28 / Thunderbird 28 / SeaMonkey 2.25 / Firefox OS 1.3)之前,<code>Object.getOwnPropertyNames</code> 不会获取到 <a href="Reference/Global_Objects/Error" title="通过Error的构造器可以创建一个错误对象。当运行时错误产生时Error的实例对象会被抛出。Error对象也可用于用户自定义的异常的基础对象。下面列出了各种内建的标准错误类型。"><code>Error</code></a> 对象的属性。该 bug 在后面的版本修复了 (<a class="external" href="https://bugzilla.mozilla.org/show_bug.cgi?id=724768" rel="noopener" title="FIXED: Object.getOwnPropertyNames does not see unresolved properties of Error objects">bug 724768</a>)。</p>
<h2 id="See_also" name="See_also" style="margin-bottom: 20px; line-height: 30px;">相关链接</h2>
<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Enumerability_and_ownership_of_properties" title="Enumerability_and_ownership_of_properties">Enumerability and ownership of properties</a></li>
<li><a href="Reference/Global_Objects/Object/hasOwnProperty" title="hasOwnProperty() 方法会返回一个布尔值,指示对象自身属性中是否具有指定的属性"><code>Object.prototype.hasOwnProperty</code></a></li>
<li><a href="Reference/Global_Objects/Object/propertyIsEnumerable" title="propertyIsEnumerable() 方法返回一个布尔值,表示指定的属性是否可枚举。"><code>Object.prototype.propertyIsEnumerable</code></a></li>
<li><a href="Reference/Global_Objects/Object/create" title="Object.create()方法创建一个新对象使用现有的对象来提供新创建的对象的__proto__。 (请打开浏览器控制台以查看运行结果。)"><code>Object.create</code></a></li>
<li><a href="Reference/Global_Objects/Object/keys" title="Object.keys() 方法会返回一个由一个给定对象的自身可枚举属性组成的数组,数组中属性名的排列顺序和使用 for...in 循环遍历该对象时返回的顺序一致 。"><code>Object.keys</code></a></li>
<li><a href="Reference/Global_Objects/Array/forEach" title="forEach() 方法对数组的每个元素执行一次提供的函数。"><code>Array.forEach()</code></a></li>
</ul>
</article>