{"id":2148,"date":"2012-01-04T22:01:04","date_gmt":"2012-01-04T14:01:04","guid":{"rendered":"http:\/\/www.zhangxinxu.com\/wordpress\/?p=2148"},"modified":"2018-01-02T01:08:10","modified_gmt":"2018-01-01T17:08:10","slug":"introducing-ecmascript-5-1","status":"publish","type":"post","link":"https:\/\/www.zhangxinxu.com\/wordpress\/2012\/01\/introducing-ecmascript-5-1\/","title":{"rendered":"\u7ffb\u8bd1\uff1aECMAScript 5.1\u7b80\u4ecb"},"content":{"rendered":"<p>by <a href=\"http:\/\/www.zhangxinxu.com\/\">zhangxinxu<\/a> from <a href=\"http:\/\/www.zhangxinxu.com\/\">http:\/\/www.zhangxinxu.com<\/a><br \/>\n\u672c\u6587\u5730\u5740\uff1a<a href=\"http:\/\/www.zhangxinxu.com\/wordpress\/?p=2148\">http:\/\/www.zhangxinxu.com\/wordpress\/?p=2148<\/a><\/p>\n<style>.entry .note{margin:.5em 0; padding: .5em; background-color:#f5f5f5; border: 2px solid #ccc; border-radius: .5em; font-size:.84em!important;}.note:hover{border-color:#bbb;}.comment{color:green;}.keyword{color:blue;}.number{color:#f0f;}.string{color:#069;}.literal{color:#F30;}pre code{font-size:1em;}<\/style>\n<div id=\"link\">\n\u539f\u6587\u5730\u5740\uff1a<a href=\"http:\/\/dev.opera.com\/articles\/view\/introducing-ecmascript-5-1\/\">Introducing ECMAScript 5.1<\/a><br \/>\n\u7ffb\u8bd1\u7f16\u8f91\uff1a<a href=\"http:\/\/www.zhangxinxu.com\/\">\u5f20\u946b\u65ed<\/a>\n<\/div>\n<h3>\u5185\u5bb9\u5bfc\u8bfb\uff1a<\/h3>\n<ol>\n<li><a href=\"#introduction\">\u7b80\u4ecb<\/a><\/li>\n<li><a href=\"#browser-support\">\u6d4f\u89c8\u5668\u652f\u6301<\/a><\/li>\n<li><a href=\"#strict-mode\">ES5\u7684\u4e25\u683c\u6a21\u5f0f<\/a><\/li>\n<li><a href=\"#json\">JSON<\/a>\n    <\/li>\n<li><a href=\"#object-additions\">\u6dfb\u52a0\u5bf9\u8c61<\/a><\/li>\n<li><a href=\"#array-extras\">\u989d\u5916\u7684\u6570\u7ec4<\/a><\/li>\n<li><a href=\"#function-bind\">Function.prototype.bind<\/a><\/li>\n<li><a href=\"#further-reading\">\u8865\u5145\u53c2\u8003<\/a><\/li>\n<\/ol>\n<h3 id=\"introduction\">\u7b80\u4ecb<\/h3>\n<p>ECMAScript 5.1 (\u6216\u4ec5 ES5) \u662fECMAScript(\u57fa\u4e8eJavaScript\u7684\u89c4\u8303)\u6807\u51c6\u6700\u65b0\u4fee\u6b63\u3002 \u4e0eHTML5\u89c4\u8303\u8fdb\u7a0b\u672c\u8d28\u7c7b\u4f3c\uff0cES5\u901a\u8fc7\u5bf9\u73b0\u6709JavaScript\u65b9\u6cd5\u6dfb\u52a0\u8bed\u53e5\u548c\u539f\u751fECMAScript\u5bf9\u8c61\u505a\u5408\u5e76\u5b9e\u73b0\u6807\u51c6\u5316\u3002ES5\u8fd8\u5f15\u5165\u4e86\u4e00\u4e2a\u8bed\u6cd5\u7684\u4e25\u683c\u53d8\u79cd\uff0c\u88ab\u79f0\u4e3a&#8221;\u4e25\u683c\u6a21\u5f0f(strict mode)&#8221;\u3002<\/p>\n<p>\u672c\u6587\u6211\u4eec\u5c06\u4ecb\u7ecd\u4e00\u4e9b\u6709\u7528\u7684\u6539\u53d8\u548c\u6dfb\u52a0\u3002\u5173\u4e8e\u5b8c\u6574\u5217\u8868\uff0c\u8bf7\u53c2\u8003<a href=\"http:\/\/www.ecma-international.org\/publications\/files\/ECMA-ST\/ECMA-262.pdf\">\u5b98\u65b9ECMAScript\u8bed\u8a00\u89c4\u8303<\/a>\u9644\u5f55D\u548cE (PDF\u4e0b\u8f7d, 3MB)\uff0c\u6216\u8005\u67e5\u770b<a href=\"http:\/\/www.ecmascript.org\/\">http:\/\/www.ecmascript.org\/<\/a>; \u60a8\u8fd8\u53ef\u4ee5\u4ee5HTML\u5f62\u5f0f\u67e5\u770b &#8211; <a href=\"http:\/\/es5.github.com\/\">Michael[tm] Smith\u975e\u5b98\u65b9\u7684HTML\u7248\u672c\u8bf4\u660e<\/a>\u3002<\/p>\n<h3 id=\"browser-support\">\u6d4f\u89c8\u5668\u652f\u6301<\/h3>\n<p>\u968f\u7740Opera 11.60\u7684\u53d1\u5e03, \u6240\u67095\u5927\u6d4f\u89c8\u5668\u90fd\u652f\u6301ES5, \u9664\u4e86\u4e00\u4e9b<a href=\"http:\/\/kristopolous.blogspot.com\/2011\/11\/winners-are-opera-ie-firefox-chrome.html\">\u5b9e\u73b0\u7684bugs<\/a>. \u9664\u975e\u53e6\u6709\u8bf4\u660e\uff0c\u672c\u6587\u4e2d\u63d0\u5230\u7684\u7684\u4e00\u5207\u53ef\u4ee5\u7528\u5728\u4ee5\u4e0b\u6d4f\u89c8\u5668\u7248\u672c\uff08\u6216\u66f4\u9ad8\uff09\uff1a<\/p>\n<ul id=\"ul\">\n<li>Opera 11.60<\/li>\n<li>Internet Explorer 9*<\/li>\n<li>Firefox 4<\/li>\n<li>Safari 5.1**<\/li>\n<li>Chrome 13<\/li>\n<\/ul>\n<p class=\"note\">* <a href=\"http:\/\/msdn.microsoft.com\/en-us\/library\/hh673540%28v=VS.85%29.aspx\">IE9\u4e0d\u652f\u6301\u4e25\u683c\u6a21\u5f0f<\/a> \u2014 IE10 \u6dfb\u52a0<\/p>\n<p class=\"note\">** Safari 5.1 \u4ecd\u4e0d\u652f\u6301 <code>Function.prototype.bind<\/code>, \u5c3d\u7ba1 <a href=\"https:\/\/bugs.webkit.org\/show_bug.cgi?id=26382\"><code>Function.prototype.bind<\/code>\u73b0\u5728\u5df2\u7ecf\u88abWebkit\u6240\u652f\u6301<\/a>\u3002<\/p>\n<p>\u5bf9\u4e8e\u65e7\u7248\u6d4f\u89c8\u5668\u7684\u652f\u6301\u4fe1\u606f\uff0c\u60a8\u53ef\u4ee5\u67e5\u770bJuriy Zaytsev\u5f88\u8d5e\u7684 <a href=\"http:\/\/kangax.github.com\/es5-compat-table\/\">ECMAScript 5 \u517c\u5bb9\u6027\u8868<\/a>\u3002\n<\/p>\n<h3 id=\"strict-mode\">ES5\u7684\u4e25\u683c\u6a21\u5f0f<\/h3>\n<p>\u4e25\u683c\u6a21\u5f0f\u7ed9\u4f5c\u8005\u63d0\u4f9b\u4e86\u9009\u62e9\u4e00\u4e2a\u9650\u5236\u6027\u66f4\u5f3a\u8bed\u8a00\u53d8\u79cd\u7684\u65b9\u5f0f\u2014\u2014\u7ed9\u4f5c\u8005\u63d0\u4f9b\u989d\u5916\u7684\u53ef\u9760\u6027\u7ed9\u7528\u6237\u63d0\u4f9b\u989d\u5916\u7684\u5b89\u5168\u6027\u3002\u5728JS\u6587\u4ef6\u6216\u662f\u51fd\u6570\u7684\u9876\u90e8\u6dfb\u52a0<code>\"use strict\"<\/code>\u5373\u53ef\u542f\u7528\u4e25\u683c\u6a21\u5f0f\u3002\u56e0\u4e3a<code>\"use strict\"<\/code>\u5c31\u662f\u4e2a\u5b57\u7b26\u4e32\uff0c\u56e0\u6b64\u5176\u4f1a\u88ab\u65e7\u7248\u6d4f\u89c8\u5668\u5b89\u5168\u5730\u5ffd\u89c6\u3002<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"undefined\">\"use strict\";<\/code><\/pre>\n<\/div>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\"><span class=\"function\"><span class=\"keyword\">function<\/span> <span class=\"title\">strict<\/span><span class=\"params\">()<\/span>{<\/span>\n  <span class=\"string\">\"use strict\"<\/span>;\n  <span class=\"comment\">\/\/...<\/span>\n}\n\n<span class=\"function\"><span class=\"keyword\">function<\/span> <span class=\"title\">sloppy<\/span><span class=\"params\">()<\/span>{<\/span>\n  eval(<span class=\"string\">\"window.foo = 'bar'\"<\/span>);\n}<\/code><\/pre>\n<\/div>\n<p>\u5728\u4e25\u683c\u6a21\u5f0f\u4e0b\u8fd0\u884c\u811a\u672c\uff0c\u4e0d\u5c11\u5bfc\u81f4\u63d0\u9192\u6216buggy\u884c\u4e3a\u7684\u4e8b\u60c5\u4f1a\u629b\u51fa\u9519\u8bef\uff0c\u4f8b\u5982\uff1a<\/p>\n<ul id=\"ul\">\n<li>\u672a\u58f0\u660e\u7684\u53d8\u91cf\u8d4b\u503c\u629b\u51fa\u4e00\u4e2a<code>ReferenceError<\/code>, \u800c\u4e0d\u662f\u521b\u5efa\u4e00\u4e2a\u5168\u5c40\u53d8\u91cf\u3002<\/li>\n<li>\u4e0d\u6b62\u4e00\u6b21\u5bf9\u5bf9\u8c61\u5b57\u9762\u91cf\u5206\u914d\u76f8\u540c\u7684\u5c5e\u6027\u4f1a\u629b\u51fa<code>SyntaxError<\/code>.<\/li>\n<li>\u4f7f\u7528<code>with<\/code>\u8bed\u53e5\u629b\u51fa<code>SyntaxError<\/code>.<\/li>\n<\/ul>\n<p><a href=\"http:\/\/msdn.microsoft.com\/en-us\/library\/br230269%28v=vs.94%29.aspx\">MDSN\u7684\u4e25\u683c\u6a21\u5f0f\u6587\u7ae0<\/a>\u6709\u4e2a\u5173\u4e8e\u6240\u6709\u8fd9\u4e9b\u5dee\u5f02\u5f88\u6709\u7528\u7684\u603b\u7ed3\u8868\u683c\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/image.zhangxinxu.com\/image\/blog\/201201\/2012-01-04_180104.png\" width=\"579\" height=\"315\" \/><\/p>\n<h3 id=\"json\">JSON<\/h3>\n<p>ES5\u63d0\u4f9b\u4e00\u4e2a\u5168\u5c40\u7684<code>JSON<\/code>\u5bf9\u8c61\uff0c\u7528\u6765\u5e8f\u5217\u5316(<code>JSON.stringify<\/code>)\u548c\u53cd\u5e8f\u5217\u5316(JSON.parse)\u5bf9\u8c61\u4e3aJSON\u683c\u5f0f\u3002<\/p>\n<p class=\"not\">\u5bf9\u4e8e\u8001\u7684\u6d4f\u89c8\u5668\uff0c\u53ef\u4ee5\u8003\u8651\u4f7f\u7528Douglas Crockford\u7684<a href=\"https:\/\/github.com\/douglascrockford\/JSON-js\/blob\/master\/json2.js\">json2.js<\/a>, \u53ef\u4ee5\u8ba9\u65e7\u7684\u6d4f\u89c8\u5668\u5b9e\u73b0\u540c\u6837\u7684\u529f\u80fd\uff08\u539f\u59cb\u652f\u6301\u529f\u80fd\u6d4b\u8bd5\u540e\uff09\u3002<\/p>\n<p><strong><code>JSON.parse(text [, reviver])<\/code><\/strong><\/p>\n<p><code>JSON.parse<\/code>\u63a5\u53d7\u6587\u672c(JSON\u683c\u5f0f)\u5e76\u8f6c\u6362\u6210\u4e00\u4e2aECMAScript\u503c\u3002\u8be5\u53ef\u9009\u7684reviver\u53c2\u6570\u662f\u6709\u5e26\u6709<code>key<\/code>\u548c<code>value<\/code>\u4e24\u4e2a\u53c2\u6570\u7684\u51fd\u6570\uff0c\u5176\u4f5c\u7528\u4e8e\u7ed3\u679c\u2014\u2014\u8ba9\u8fc7\u6ee4\u548c\u8f6c\u6362\u8fd4\u56de\u503c\u6210\u4e3a\u53ef\u80fd\u3002<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\">&gt;&gt; <span class=\"keyword\">var<\/span> result = JSON.parse(<span class=\"string\">'{\"a\": 1, \"b\": \"2\"}'<\/span>);\nObject\n\n&gt;&gt; result.b\n<span class=\"string\">\"2\"<\/span><\/code><\/pre>\n<\/div>\n<p>\u5982\u679c\u6211\u4eec\u60f3\u786e\u4fdd\u89e3\u6790\u7684\u503c\u662f\u4e2a\u6574\u6570\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528reviver\u65b9\u6cd5\u3002<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\"><span class=\"keyword\">var<\/span> result = JSON.parse(<span class=\"string\">'{\"a\": 1, \"b\": \"2\"}'<\/span>, <span class=\"function\"><span class=\"keyword\">function<\/span><span class=\"params\">(key, value)<\/span>{<\/span>\n  <span class=\"keyword\">if<\/span> (<span class=\"keyword\">typeof<\/span> value == <span class=\"string\">'string'<\/span>){\n    <span class=\"keyword\">return<\/span> parseInt(value);\n  } <span class=\"keyword\">else<\/span> {\n    <span class=\"keyword\">return<\/span> value; \n  }\n})\n\n&gt;&gt; result.b\n<span class=\"number\">2<\/span><\/code><\/pre>\n<\/div>\n<p><strong><code>JSON.stringify(value [, replacer [, space]])<\/code><\/strong><\/p>\n<p><code>JSON.stringify<\/code>\u5141\u8bb8\u4f5c\u8005\u63a5\u53d7\u4e00\u4e2aECMAScript\u503c\u7136\u540e\u8f6c\u6362\u6210JSON\u683c\u5f0f\u7684\u5b57\u7b26\u4e32\u3002 \u5728\u5176\u6700\u7b80\u5355\u7684\u5f62\u5f0f\u4e2d\uff0c<code>JSON.stringify<\/code>\u63a5\u53d7\u4e00\u4e2a\u503c\u8fd4\u56de\u4e00\u4e2a\u5b57\u7b26\u4e32\uff0c<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\">&gt;&gt;&gt; <span class=\"keyword\">var<\/span> mike = JSON.stringify({mike: <span class=\"string\">\"taylor\"<\/span>})\nundefined\n\n&gt;&gt; mike\n<span class=\"string\">'{\"mike\": \"taylor\"}'<\/span>\n\n&gt;&gt; <span class=\"keyword\">typeof<\/span> mike\n<span class=\"string\">\"string\"<\/span><\/code><\/pre>\n<\/div>\n<p>\u5982\u679c\u6211\u4eec\u9700\u8981\u6539\u53d8\u503c\u5b57\u7b26\u4e32\u5316\u7684\u65b9\u5f0f\uff0c\u6216\u662f\u5bf9\u6211\u4eec\u9009\u62e9\u7684\u63d0\u4f9b\u8fc7\u6ee4\uff0c\u6211\u4eec\u53ef\u4ee5\u5c06\u5176\u4f20\u7ed9replacer\u51fd\u6570\u3002\u4f8b\u5982\uff0c\u6211\u4eec\u60f3\u8fc7\u6ee4\u51fa\u5373\u5c06\u88ab\u5b57\u7b26\u4e32\u5316\u7684\u5bf9\u8c61\u4e2d\u503c\u4e3a13\u7684\u5c5e\u6027\uff1a<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\"><span class=\"keyword\">var<\/span> nums = {\n  <span class=\"string\">\"first\"<\/span>: <span class=\"number\">7<\/span>,\n  <span class=\"string\">\"second\"<\/span>: <span class=\"number\">14<\/span>,\n  <span class=\"string\">\"third\"<\/span>: <span class=\"number\">13<\/span>\n}\n\n<span class=\"keyword\">var<\/span> luckyNums = JSON.stringify(nums, <span class=\"function\"><span class=\"keyword\">function<\/span><span class=\"params\">(key, value)<\/span>{<\/span>\n  <span class=\"keyword\">if<\/span> (value == <span class=\"number\">13<\/span>) {\n    <span class=\"keyword\">return<\/span> undefined;\n  } <span class=\"keyword\">else<\/span> {\n    <span class=\"keyword\">return<\/span> value;\n  }\n});\n\n&gt;&gt; luckyNums\n<span class=\"string\">'{\"first\": 7, \"second\": 14}'<\/span><\/code><\/pre>\n<\/div>\n<p>\u5982\u679creplacer\u65b9\u6cd5\u8fd4\u56de<code>undefined<\/code>, \u5219\u952e\u503c\u5bf9\u5c31\u4e0d\u4f1a\u5305\u542b\u5728\u6700\u7ec8\u7684JSON\u4e2d\u3002\u6211\u4eec\u540c\u6837\u53ef\u4ee5\u4f20\u9012\u4e00\u4e2aspace\u53c2\u6570\u4ee5\u4fbf\u83b7\u5f97\u8fd4\u56de\u7ed3\u679c\u7684\u53ef\u8bfb\u6027\u5e2e\u52a9\u3002space\u53c2\u6570\u53ef\u4ee5\u662f\u4e2a\u6570\u5b57\uff0c\u8868\u660e\u4e86\u4f5c\u7f29\u8fdb\u7684JSON\u5b57\u7b26\u4e32\u6216\u5b57\u7b26\u4e32\u6bcf\u4e2a\u6c34\u5e73\u4e0a\u7f29\u8fdb\u7684\u7a7a\u683c\u6570\u3002\u5982\u679c\u53c2\u6570\u662f\u4e2a\u8d85\u8fc710\u7684\u6570\u503c\uff0c\u6216\u662f\u8d85\u8fc710\u4e2a\u5b57\u7b26\u7684\u5b57\u7b26\u4e32\uff0c\u5c06\u5bfc\u81f4\u53d6\u6570\u503c10\u6216\u662f\u622a\u53d6\u524d10\u4e2a\u5b57\u7b26\u3002<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"php\"><span class=\"keyword\">var<\/span> luckyNums = JSON.stringify(nums, <span class=\"keyword\">function<\/span>(key, value) {\n  <span class=\"keyword\">if<\/span> (value == <span class=\"number\">13<\/span>) {\n    <span class=\"keyword\">return<\/span> undefined;\n  } <span class=\"keyword\">else<\/span> {\n    <span class=\"keyword\">return<\/span> value;\n  }\n}, <span class=\"number\">2<\/span>);\n\n&gt;&gt; luckyNums\n<span class=\"string\">'{\n  \"first\":7,\n  \"second\":14\n}'<\/span><\/code><\/pre>\n<\/div>\n<h3 id=\"object-additions\">\u9644\u52a0\u5bf9\u8c61<\/h3>\n<p>\u4e0b\u9762\u7684\u65b9\u6cd5\u662f\u6dfb\u52a0\u5230<code>Object<\/code>\u4e0a\u7684\u6784\u9020\u5668\uff1a<\/p>\n<ul id=\"ul\">\n<li><code>Object.getPrototypeOf<\/code><\/li>\n<li><code>Object.getOwnPropertyDescriptor<\/code><\/li>\n<li><code>Object.getOwnPropertyNames<\/code><\/li>\n<li><code>Object.create<\/code><\/li>\n<li><code>Object.defineProperty<\/code><\/li>\n<li><code>Object.defineProperties<\/code><\/li>\n<li><code>Object.seal<\/code><\/li>\n<li><code>Object.freeze<\/code><\/li>\n<li><code>Object.preventExtensions<\/code><\/li>\n<li><code>Object.isSealed<\/code><\/li>\n<li><code>Object.isFrozen<\/code><\/li>\n<li><code>Object.isExtensible<\/code><\/li>\n<li><code>Object.keys<\/code><\/li>\n<\/ul>\n<p>\u8fd9\u4e9b\u65b0\u589e\u7684\u597d\u5904\u4e4b\u4e00\u662f\u5bf9\u8c61\u7684\u5c5e\u6027\u6709\u4e86\u66f4\u591a\u63a7\u5236\uff0c\u4f8b\u5982\u54ea\u4e9b\u662f\u5141\u8bb8\u88ab\u4fee\u6539\u7684\uff0c\u54ea\u4e9b\u662f\u53ef\u4ee5\u679a\u4e3e\u7684\uff0c\u54ea\u4e9b\u662f\u53ef\u4ee5\u5220\u9664\u7684\u7b49\u3002\u8fd9\u4e2a\u7684\u5b9e\u73b0\u901a\u8fc7\u7a0b\u5e8f\u8bbf\u95ee\u5bf9\u8c61\u7684<em>\u5c5e\u6027\u63cf\u8ff0\u7b26(property descriptors)<\/em>. \u4f8b\u5982\uff1a<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\"><span class=\"keyword\">var<\/span> cat = {};\n\nObject.defineProperty(cat, <span class=\"string\">\"name\"<\/span>, {\n  value: <span class=\"string\">\"Maru\"<\/span>,\n  writable: <span class=\"literal\">false<\/span>,\n  enumerable: <span class=\"literal\">true<\/span>,\n  configurable: <span class=\"literal\">false<\/span>\n});\n\nObject.defineProperty(cat, <span class=\"string\">\"skill\"<\/span>, {\n  value: <span class=\"string\">\"exploring boxes\"<\/span>,\n  writable: <span class=\"literal\">true<\/span>,\n  enumerable: <span class=\"literal\">true<\/span>,\n  configurable: <span class=\"literal\">true<\/span>\n});<\/code><\/pre>\n<\/div>\n<p>\u5bf9\u4e8e\u6211\u4eec\u7684<code>cat<\/code>\u5bf9\u8c61, \u5176\u540d\u5b57<code>name<\/code>\u4e0d\u80fd\u88ab\u6539\u53d8\uff0c\u4f46\u662f\u4f1a\u51fa\u73b0\u5728<code>for-in<\/code>\u5faa\u73af\u4e2d\u3002\u5728\u5176\u4ed6\u65b9\u9762\uff0cMaru\u64c5\u957f\u63a2\u7d22\u76d2\u5b50(exploring boxes), \u4f46\u662f\u53ef\u4ee5\u5728\u5c06\u6765\u6539\u53d8\uff0c\u56e0\u4e3a<code>skill<\/code>\u5c5e\u6027\u662f<code>writable<\/code>\u548c<code>configurable<\/code>\u7684\u3002<\/p>\n<p>\u5728\u4e4b\u540e\u7684\u6587\u7ae0\u6211\u4eec\u5c06\u8be6\u7ec6\u63a2\u8ba8\u6240\u6709\u9644\u52a0\u7684\u5bf9\u8c61\u3002<\/p>\n<h3 id=\"array-extras\">\u989d\u5916\u7684\u6570\u7ec4<\/h3>\n<p>\u4ee5\u4e0b\u65b9\u6cd5\u6dfb\u52a0\u5230\u4e86Array<code>prototype<\/code>\u5bf9\u8c61\u4e0a:<\/p>\n<ul id=\"ul\">\n<li><code>Array.prototype.indexOf<\/code><\/li>\n<li><code>Array.prototype.lastIndexOf<\/code><\/li>\n<li><code>Array.prototype.every<\/code><\/li>\n<li><code>Array.prototype.some<\/code><\/li>\n<li><code>Array.prototype.forEach<\/code><\/li>\n<li><code>Array.prototype.map<\/code><\/li>\n<li><code>Array.prototype.filter<\/code><\/li>\n<li><code>Array.prototype.reduce<\/code><\/li>\n<li><code>Array.prototype.reduceRight<\/code><\/li>\n<\/ul>\n<p>\u5173\u4e8e<a href=\"http:\/\/dev.opera.com\/articles\/view\/javascript-array-extras-in-detail\/\">ES5\u6570\u7ec4&#8221;extras&#8221;<\/a> Dmitry Soshnikov\u5199\u8fc7\u4e00\u7bc7\u6709\u6df1\u5ea6\u7684\u53c2\u8003\u6587\u7ae0\u3002<\/p>\n<p>Dmitry\u7684\u6587\u7ae0\u4e2d\u6709\u4e00\u4e2a\u6ca1\u6709\u63d0\u5230\uff0c\u5c31\u662f<code>Array.isArray<\/code>, \u6b63\u5982\u4f60\u770b\u5230\u7684\uff0c\u8fd9\u53ae\u76f4\u63a5\u5199\u5728\u4e86<code>Array<\/code>\u6784\u9020\u5668\u4e0a\uff0c\u800c\u4e0d\u662f<code>prototype<\/code>\u5bf9\u8c61\u4e0a\u3002<code>Array.isArray<\/code>\u4f1a\u6309\u7167\u4f60\u6240\u671f\u5f85\u7684\u90a3\u6837\u53bb\u505a \u2014 \u8fd9\u662f\u4e00\u4e2a\u6839\u636e\u53c2\u6570\u7684[[Class]]\u5185\u90e8\u5c5e\u6027\u662f\u5426\u662f&#8221;Array&#8221;\u8fd4\u56de<code>true<\/code>\u6216<code>false<\/code>.<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"php\"><span class=\"keyword\">Array<\/span>.isArray(<span class=\"string\">\"NO U\"<\/span>)\n&gt;&gt; <span class=\"keyword\">false<\/span>\n\n<span class=\"keyword\">Array<\/span>.isArray([<span class=\"string\">\"NO\"<\/span>, <span class=\"string\">\"U\"<\/span>])\n&gt;&gt; <span class=\"keyword\">true<\/span><\/code><\/pre>\n<\/div>\n<p>\u5728ES3\u4e2d\uff0c\u552f\u4e00\u53ef\u9760\u7684\u786e\u5b9a\u4e00\u4e2a\u503c\u662f\u6570\u7ec4\u7684\u65b9\u5f0f\u5c31\u662f\u4f7f\u7528<a href=\"http:\/\/www.songhaysystem.com\/kb\/number\/2076072056\/subject\/htmlscrp\">&#8220;the Miller Device&#8221;<\/a>, \u5373\u6bd4\u5bf9\u4e00\u4e2a\u6570\u7ec4\u5176\u5185\u5728\u7684<code>[[Class]]<\/code>\u5c5e\u6027\u3002<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"perl\">Object.<span class=\"keyword\">prototype<\/span>.toString.apply(value) === <span class=\"string\">'[object Array]'<\/span><\/code><\/pre>\n<\/div>\n<h3 id=\"function-bind\"><code>Function.prototype.bind(thisArg [, arg1 [, arg2, \u2026]])<\/code><\/h3>\n<p><code>Function.prototype.bind<\/code>\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u51fd\u6570\u5bf9\u8c61\uff0c\u8be5\u51fd\u6570\u5bf9\u8c61\u7684<em>this<\/em>\u7ed1\u5b9a\u5230\u4e86<code>thisArg<\/code>\u53c2\u6570\u4e0a\u3002\u4ece\u672c\u8d28\u4e0a\u8bb2\uff0c\u8fd9\u5141\u8bb8\u4f60\u5728\u5176\u4ed6\u5bf9\u8c61\u94fe\u4e2d\u6267\u884c\u4e00\u4e2a\u51fd\u6570\u3002<\/p>\n<div class=\"zxx_code\">\n<pre><code class=\"javascript\"><span class=\"function\"><span class=\"keyword\">function<\/span> <span class=\"title\">locate<\/span><span class=\"params\">()<\/span>{<\/span>\n  console.log(<span class=\"keyword\">this<\/span>.location);\n}\n\n<span class=\"function\"><span class=\"keyword\">function<\/span> <span class=\"title\">Maru<\/span><span class=\"params\">(location)<\/span>{<\/span>\n  <span class=\"keyword\">this<\/span>.location = location;\n}\n\n<span class=\"keyword\">var<\/span> kitty = <span class=\"keyword\">new<\/span> Maru(<span class=\"string\">\"cardboard box\"<\/span>);\n\n<span class=\"keyword\">var<\/span> locateMaru = locate.bind(kitty);\n\nlocateMaru();<\/code><\/pre>\n<\/div>\n<p>\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u5c06Maru\u5bf9\u8c61\u7684\u4e0a\u4e0b\u6587\u5e94\u7528\u5728<code>location<\/code>\u51fd\u6570\u4e2d\u3002\u56e0\u4e3a<code>location<\/code>\u662f\u4e2a\u5168\u5c40\u5bf9\u8c61\u7684\u5c5e\u6027\uff0c\u5176<code>this<\/code>\u503c\u5c31\u662f\u5168\u5c40\u5bf9\u8c61(<code>window<\/code>)\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u5411\u4e0a\u5bfb\u627ecat, \u5e76\u4e0d\u662f<code>Location<\/code>\u5bf9\u8c61\uff0c\u56e0\u4e3a\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u7ed1\u5b9a\u7684\u603b\u662f<code>kitty<\/code>\u7684<code>this<\/code>\u503c\u521b\u5efa\u4e00\u4e2a\u65b0\u65b9\u6cd5<code>locateMaru<\/code>.<\/p>\n<h3 id=\"further-reading\">\u8865\u5145\u53c2\u8003<\/h3>\n<ul id=\"ul\">\n<li><a href=\"http:\/\/ejohn.org\/blog\/ecmascript-5-objects-and-properties\/\">ECMAScript 5 \u5bf9\u8c61\u548c\u5c5e\u6027<\/a> by John Resig<\/li>\n<li><a href=\"http:\/\/yehudakatz.com\/2011\/08\/11\/understanding-javascript-function-invocation-and-this\/\">\u7406\u89e3JavaScript\u51fd\u6570\u8c03\u7528\u548c&#8221;this&#8221;<\/a> by Yehuda Katz<\/li>\n<li><a href=\"http:\/\/javascriptweblog.wordpress.com\/2011\/05\/03\/javascript-strict-mode\/\">JavaScript\u4e25\u683c\u6a21\u5f0f<\/a> by Angus Croll<\/li>\n<li>ECMA-262-5\u8be6\u7ec6 <a href=\"http:\/\/dmitrysoshnikov.com\/ecmascript\/es5-chapter-0-introduction\/\">\u4ecb\u7ecd<\/a> by Dmitry Soshnikov<\/li>\n<li><a href=\"http:\/\/kangax.github.com\/es5-compat-table\/\">ECMAScript 5 \u517c\u5bb9\u6027\u8868<\/a> by Juriy Zaytsev<\/li>\n<\/ul>\n<p id=\"license\" class=\"info\">\u672c\u6587\u8bb8\u53ef\u81ea<a href=\"http:\/\/creativecommons.org\/licenses\/by\/3.0\/\" rel=\"license\">Creative Commons Attribution 3.0 Unported<\/a>\u8bb8\u53ef\u3002<\/p>\n<p>\u672c\u6587\u4e3a\u539f\u521b\u6587\u7ae0\uff0c\u8f6c\u8f7d\u8bf7\u6ce8\u660e\u6765\u81ea<a href=\"http:\/\/www.zhangxinxu.com\/\">\u5f20\u946b\u65ed-\u946b\u7a7a\u95f4-\u946b\u751f\u6d3b<\/a>[<a href=\"http:\/\/www.zhangxinxu.com\/\">http:\/\/www.zhangxinxu.com<\/a>]<br \/>\n\u672c\u6587\u5730\u5740\uff1a<a href=\"http:\/\/www.zhangxinxu.com\/wordpress\/?p=2148\">http:\/\/www.zhangxinxu.com\/wordpress\/?p=2148<\/a><\/p>\n<p>\uff08\u672c\u7bc7\u5b8c\uff09<\/p>\n","protected":false},"excerpt":{"rendered":"<p>ECMAScript 5.1 (\u6216\u4ec5 ES5) \u662fECMAScript(\u57fa\u4e8eJavaScript\u7684\u89c4\u8303)\u6807\u51c6\u6700\u65b0\u4fee\u6b63\u3002 \u4e0eHTML5\u89c4\u8303\u8fdb\u7a0b\u672c\u8d28\u7c7b\u4f3c\uff0cES5\u901a\u8fc7\u5bf9\u73b0\u6709JavaScript\u65b9\u6cd5\u6dfb\u52a0\u8bed\u53e5\u548c\u539f\u751fECMAScript\u5bf9\u8c61\u505a\u5408\u5e76\u5b9e\u73b0\u6807\u51c6\u5316\u3002ES5\u8fd8\u5f15\u5165\u4e86\u4e00\u4e2a\u8bed\u6cd5\u7684\u4e25\u683c\u53d8\u79cd\uff0c\u88ab\u79f0\u4e3a\u201d\u4e25\u683c\u6a21\u5f0f(strict mode)\u201d\u3002<br \/>\n\u672c\u6587\u6211\u4eec\u5c06\u4ecb\u7ecd\u4e00\u4e9b\u6709\u7528\u7684\u6539\u53d8\u548c\u6dfb\u52a0\u3002\u5173\u4e8e\u5b8c\u6574\u5217\u8868\uff0c\u2026\u2026<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[198],"tags":[670,667,668,13,553,509,669],"_links":{"self":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/2148"}],"collection":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/comments?post=2148"}],"version-history":[{"count":0,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/2148\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/media?parent=2148"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/categories?post=2148"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/tags?post=2148"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}