{"id":9984,"date":"2021-07-01T23:15:10","date_gmt":"2021-07-01T15:15:10","guid":{"rendered":"https:\/\/www.zhangxinxu.com\/wordpress\/?p=9984"},"modified":"2021-07-01T23:15:10","modified_gmt":"2021-07-01T15:15:10","slug":"js-proxy-reflect","status":"publish","type":"post","link":"https:\/\/www.zhangxinxu.com\/wordpress\/2021\/07\/js-proxy-reflect\/","title":{"rendered":"Proxy\u662f\u4ee3\u7406\uff0cReflect\u662f\u5e72\u561b\u7528\u7684\uff1f"},"content":{"rendered":"<p>by <a href=\"https:\/\/www.zhangxinxu.com\/\">zhangxinxu<\/a> from <a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/?p=9984\">https:\/\/www.zhangxinxu.com\/wordpress\/?p=9984<\/a><br \/>\n\u672c\u6587\u6b22\u8fce\u5206\u4eab\u4e0e\u805a\u5408\uff0c\u5168\u6587\u8f6c\u8f7d\u5c31\u4e0d\u5fc5\u4e86\uff0c\u5c0a\u91cd\u7248\u6743\uff0c\u5708\u5b50\u5c31\u8fd9\u4e48\u5927\uff0c\u82e5\u6025\u7528\u53ef\u4ee5\u8054\u7cfb\u6388\u6743\u3002<\/p>\n<p><script>window.wxShareImgUrl = 'https:\/\/www.zhangxinxu.com\/study\/image\/share\/202107-reflect.jpg';<\/script><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202107\/reflect-cover.jpg\" width=\"480\" height=\"309\" alt=\"\u5c01\u9762\u56fe\u793a\u610f\" class=\"alignright clip thumb size-medium\" \/><\/p>\n<h3>\u4e00\u3001Reflect\u6709\u4ec0\u4e48\u7528\uff1f<\/h3>\n<p>\u4e00\u53e5\u8bdd\uff0cReflect\u6ca1\u4ec0\u4e48\u7528\uff0c\u9664\u4e86\u88c5\u88c5\u903c\uff0c\u8ba9\u4eba\u770b\u8d77\u6765\u9ad8\u5927\u4e0a\u4ee5\u5916\uff0c\u5e76\u4e0d\u5177\u6709\u4ec0\u4e48\u725b\u903c\u4e4b\u5904\u3002<\/p>\n<p>\u51c6\u786e\u8bb2\u5e94\u8be5\u662f\u8fd9\u6837\u7684\uff0cReflect\u66f4\u50cf\u662f\u4e00\u79cd\u8bed\u6cd5\u53d8\u4f53\uff0c\u5176\u6302\u5728\u7684\u6240\u6709\u65b9\u6cd5\u90fd\u80fd\u627e\u5230\u5bf9\u5e94\u7684\u539f\u59cb\u8bed\u6cd5\uff0c\u4e5f\u5c31\u662fReflect\u7684\u66ff\u4ee3\u6027\u975e\u5e38\u5f3a\u3002<\/p>\n<p>\u5176\u5b9e\u4eceReflect\u8fd9\u4e2a\u5355\u8bcd\u672c\u8eab\u5b57\u9762\u610f\u601d\u5c31\u80fd\u4f53\u4f1a\u51faReflect\u7684\u795e\u97f5\uff0cReflect\u7684\u4e2d\u6587\u610f\u601d\u662f\u201c\u53cd\u5c04\u201d\uff0c\u9633\u5149\u7167\u5728\u955c\u5b50\u4e0a\u53cd\u5c04\uff0c\u5176\u5b9e\u5149\u5b50\u8fd8\u662f\u90a3\u4e9b\u5149\u5b50\uff0c\u53ea\u662f\u53d8\u5316\u4e86\u65b9\u5411\u3002<\/p>\n<p>\u4e3e\u4f8b\u8bf4\u660e\uff1a<\/p>\n<p>Reflect\u5bf9\u8c61\u6302\u8f7d\u4e86\u5f88\u591a\u9759\u6001\u65b9\u6cd5\uff0c\u6240\u8c13\u9759\u6001\u65b9\u6cd5\uff0c\u5c31\u662f\u548c<code>Math.round()<\/code>\u8fd9\u6837\uff0c\u4e0d\u9700\u8981new\u5c31\u53ef\u4ee5\u76f4\u63a5\u4f7f\u7528\u7684\u65b9\u6cd5\u3002<\/p>\n<p>\u6bd4\u8f83\u5e38\u7528\u7684\u4e24\u4e2a\u65b9\u6cd5\u5c31\u662f<code>get()<\/code>\u548c<code>set()<\/code>\u65b9\u6cd5\uff1a<\/p>\n<pre>Reflect.get(target, propertyKey[, receiver])\r\nReflect.set(target, propertyKey, value[, receiver])<\/pre>\n<p>\u5c31\u4f5c\u7528\u800c\u8a00\uff0c\u7b49\u540c\u4e8e\uff1a<\/p>\n<pre>target[propertyKey]\r\ntarget[propertyKey] = value;<\/pre>\n<p>\u6bd4\u65b9\u8bf4\u9875\u9762\u4e0a\u6709\u4e2a\u8f93\u5165\u6846\uff0c\u5176DOM\u5bf9\u8c61\u53d8\u91cf\u662f<code>input<\/code>\uff0c\u5e73\u65f6\u6211\u4eec\u5bf9\u6574\u4e2a\u8f93\u5165\u6846\u8d4b\u503c\u4f7f\u7528\u7684\u8bed\u53e5\u591a\u534a\u662f\uff1a<\/p>\n<pre>input.value = 'zhangxinxu';<\/pre>\n<p>\u5c31\u53ef\u4ee5\u76f4\u63a5\u4f7f\u7528<code>Reflect.set()<\/code>\u65b9\u6cd5\u4ee3\u66ff\uff1a<\/p>\n<pre>Reflect.set(input, 'value', 'zhangxinxu')<\/pre>\n<p>\u6548\u679c\u662f\u4e00\u6a21\u4e00\u6837\u7684\u3002<\/p>\n<p>\u53c8\u4f8b\u5982\uff0c\u6211\u4eec\u5e0c\u671b\u5bf9<code>input<\/code>\u7684<code>value<\/code>\u5c5e\u6027\u91cd\u65b0\u5b9a\u4e49\uff0c\u4f7f\u8be5\u8f93\u5165\u6846<code>value<\/code>\u5c5e\u6027\u53d1\u751f\u53d8\u5316\u7684\u65f6\u5019\u53ef\u4ee5\u540c\u65f6\u89e6\u53d1<code>'change'<\/code>\u4e8b\u4ef6\uff0c\u4e0b\u9762\u662f\u4f7f\u7528\u5927\u5bb6\u666e\u904d\u6bd4\u8f83\u719f\u6089\u7684<code>Object.defineProperty()<\/code>\u65b9\u6cd5\u5b9e\u73b0\u7684\u793a\u610f\uff1a<\/p>\n<pre>const props = Object.getOwnPropertyDescriptor(input, 'value');\r\nObject.defineProperty(input, 'value', {\r\n    ...props,\r\n    set (v) {\r\n        let oldv = this.value;\r\n        props.set.call(this, v);\r\n        <span class=\"green\">\/\/ \u624b\u52a8\u89e6\u53d1change\u4e8b\u4ef6<\/span>\r\n        if (oldv !== v) {\r\n            this.dispatchEvent(new CustomEvent('change'));\r\n        }\r\n    }\r\n});<\/pre>\n<p>\u76f8\u5173\u4ecb\u7ecd\u53ef\u4ee5\u53c2\u89c1\u8fd9\u7bc7\u6587\u7ae0\uff1a\u201c<a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/2021\/05\/js-value-change\/\">\u8f93\u5165\u6846value\u5c5e\u6027\u8d4b\u503c\u89e6\u53d1js change\u4e8b\u4ef6\u7684\u5b9e\u73b0<\/a>\u201d<\/p>\n<p>\u4e0a\u8ff0\u4ee3\u7801\u6211\u4eec\u5b8c\u5168\u53ef\u4ee5\u4f7f\u7528Reflect\u5bf9\u8c61\u5b9e\u73b0\uff0c\u5177\u4f53\u7684JavaScript\u4ee3\u7801\u5982\u4e0b\u6240\u793a\u3002<\/p>\n<pre>const props = <span style=\"color:#cd0000;\">Reflect.getOwnPropertyDescriptor<\/span>(HTMLInputElement.prototype, 'value');\r\n<span style=\"color:#cd0000;\">Reflect.defineProperty<\/span>(input, 'value', {\r\n    ...props,\r\n    set (v) {\r\n        let oldv = this.value;\r\n        props.set.call(this, v);\r\n        <span class=\"green\">\/\/ \u624b\u52a8\u89e6\u53d1change\u4e8b\u4ef6<\/span>\r\n        if (oldv !== v) {\r\n            this.dispatchEvent(new CustomEvent('change'));\r\n        }\r\n    }\r\n});<\/pre>\n<p>\u6211\u4eec\u53ef\u4ee5\u6d4b\u8bd5\u4e0b\uff0c\u5047\u8bbe\u9875\u9762HTML\u5982\u4e0b\uff1a<\/p>\n<pre>&lt;input id=\"input\"&gt;<\/pre>\n<p>\u6d4b\u8bd5\u4ee3\u7801\u4e3a\uff1a<\/p>\n<pre>input.addEventListener('change', () => {\r\n  document.body.append('\u53d8\u5316\u5566~');\r\n});\r\n\r\ninput.value = 'zhangxinxu';<\/pre>\n<p>\u6b64\u65f6\uff0c\u5c31\u53ef\u4ee5\u770b\u5230\u9875\u9762\u4e0a\u51fa\u73b0\u4e86\u201c\u53d8\u5316\u5566~\u201d\u6587\u5b57\uff0c\u622a\u56fe\u793a\u610f\u5982\u4e0b\uff1a<\/p>\n<p>\u53ef\u4ee5\u5728\u8fd9\u4e2aJSBIN\u5730\u5740\u4f53\u9a8c\uff1a<a href=\"https:\/\/output.jsbin.com\/vugucajepa\" target=\"_blank\" rel=\"nooppener nofollow\">https:\/\/output.jsbin.com\/vugucajepa<\/a><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202107\/2021-07-01_161934.png\" width=\"254\" height=\"49\" alt=\"Reflect\u4e0evalue\u8d4b\u503c\"><\/p>\n<p><span class=\"hidden\">\/\/zxx: \u5982\u679c\u4f60\u770b\u5230\u8fd9\u6bb5\u6587\u5b57\uff0c\u8bf4\u660e\u4f60\u73b0\u5728\u8bbf\u95ee\u662f\u4f53\u9a8c\u7cdf\u7cd5\u7684\u5783\u573e\u76d7\u7248\u7f51\u7ad9\uff0c\u4f60\u53ef\u4ee5\u8bbf\u95ee\u539f\u6587\u83b7\u5f97\u5f88\u597d\u7684\u4f53\u9a8c\uff1ahttps:\/\/www.zhangxinxu.com\/wordpress\/?p=9984\uff08\u4f5c\u8005\u5f20\u946b\u65ed\uff09<\/span><\/p>\n<h3>\u4e8c\u3001\u7ec6\u5fae\u5dee\u5f02-\u8fd4\u56de\u503c<\/h3>\n<p>\u4e8b\u7269\u5b58\u5728\u5fc5\u6709\u9053\u7406\uff0c\u5982\u679cReflect\u4ec5\u4ec5\u662f\u6362\u4e86\u79cd\u8bed\u6cd5\uff0c\u5b58\u5728\u7684\u610f\u4e49\u5e76\u4e0d\u5927\uff0c\u5f88\u663e\u7136\uff0cReflect\u5bf9\u8c61\u7684\u51fa\u73b0\u5fc5\u7136\u6709\u5176\u4ed6\u7684\u8003\u91cf\u3002<\/p>\n<p>\u6211\u8ba4\u4e3a\u5176\u4e2d\u6709\u610f\u4e49\u7684\u4e00\u70b9\u5c31\u662f\u8fd4\u56de\u503c\u3002<\/p>\n<p>\u5bf9\u4e8e\u67d0\u4e2a\u5bf9\u8c61\uff0c\u8d4b\u503c\u5e76\u4e0d\u603b\u662f\u6210\u529f\u7684\u3002<\/p>\n<p>\u4f8b\u5982\uff0c\u6211\u4eec\u628a <code>input<\/code> \u7684<code>type<\/code>\u5c5e\u6027\u8bbe\u7f6e\u4e3a\u53ea\u8bfb\uff0c\u5982\u4e0b\uff1a<\/p>\n<pre>Object.defineProperty(input, 'type', {\r\n    get () {\r\n       return this.getAttribute('type') || 'text';\r\n    }\r\n});<\/pre>\n<p>\u4f20\u7edf\u7684\u4f7f\u7528\u7b49\u4e8e\u53f7\u8fdb\u884c\u7684\u5c5e\u6027\u8d4b\u503c\u5e76\u4e0d\u80fd\u77e5\u9053\u6700\u540e\u662f\u5426\u6267\u884c\u6210\u529f\uff0c\u9700\u8981\u5f00\u53d1\u8005\u81ea\u5df1\u8fdb\u884c\u8fdb\u4e00\u6b65\u7684\u68c0\u6d4b\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<pre>console.log(input.type = 'number');\r\n\r\n<span class=\"green\">\/\/ \u8f93\u51fa false<\/span>\r\nconsole.log(Reflect.set(input, 'type', 'number'));<\/pre>\n<p>\u4e0a\u9762\u4e00\u884c\u8d4b\u503c\u8fd4\u56de\u503c\u662f<code>'number'<\/code>\uff0c\u81f3\u4e8e\u6539\u53d8\u8f93\u5165\u6846\u7684<code>type<\/code>\u5c5e\u6027\u503c\u662f\u5426\u6210\u529f\uff0c\u4e0d\u5f97\u800c\u77e5\u3002<\/p>\n<p>\u4f46\u662f\u4e0b\u9762\u4e00\u884c\u8bed\u53e5\u4f7f\u7528\u7684<code>Reflect.set()<\/code>\u65b9\u6cd5\uff0c\u5c31\u53ef\u4ee5\u77e5\u9053\u662f\u5426\u8bbe\u7f6e\u6210\u529f\uff0c\u56e0\u4e3a<code>Reflect.set()<\/code>\u7684\u8fd4\u56de\u503c\u662f<code>true<\/code>\u6216\u8005<code>false<\/code>\uff08\u53ea\u8981\u53c2\u6570\u7c7b\u578b\u51c6\u786e\uff09\u3002<\/p>\n<p>\u9664\u4e86\u77e5\u9053\u6267\u884c\u7ed3\u679c\u5916\uff0cReflect\u65b9\u6cd5\u8fd8\u6709\u4e2a\u597d\u5904\uff0c\u4e0d\u4f1a\u56e0\u4e3a\u62a5\u9519\u800c\u4e2d\u65ad\u6b63\u5e38\u7684\u4ee3\u7801\u903b\u8f91\u6267\u884c\u3002<\/p>\n<p>\u4f8b\u5982\u4e0b\u9762\u7684\u4ee3\u7801\uff1a<\/p>\n<pre>(function () {\r\n    'use strict';\r\n\r\n    var frozen = { 1: 81 };\r\n    Object.freeze(frozen);\r\n\r\n    frozen[1] = 'zhangxinxu';\r\n\r\n    console.log('no log');\r\n})();<\/pre>\n<p>\u4f1a\u51fa\u73b0\u4e0b\u9762\u7684TypeError\u9519\u8bef\uff1a<\/p>\n<blockquote><p>Uncaught TypeError: Cannot assign to read only property &#8216;1&#8217; of object &#8216;#&lt;Object&gt;&#8217;<\/p><\/blockquote>\n<p>\u540e\u9762\u7684\u8bed\u53e5<code>console.log('no log')<\/code>\u5c31\u6ca1\u6709\u88ab\u6267\u884c\u3002<\/p>\n<p>\u4f46\u662f\u5982\u679c\u4f7f\u7528Reflect\u65b9\u6cd5\uff0c\u5219console\u8bed\u53e5\u662f\u53ef\u4ee5\u6267\u884c\u7684\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre>(function () {\r\n    'use strict';\r\n\r\n    var frozen = { 1: 81 };\r\n    Object.freeze(frozen);\r\n\r\n    Reflect.set(frozen, '1', 'zhangxinxu');\r\n\r\n    console.log('no log');\r\n})();<\/pre>\n<p>\u63a7\u5236\u53f0\u8fd0\u884c\u540e\u7684log\u8f93\u51fa\u503c\u5982\u4e0b\u56fe\u6240\u793a\uff1a<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202107\/2021-07-01_190503.png\" width=\"336\" height=\"262\" alt=\"log\u6b63\u5e38\u6267\u884c\u4e86\"><\/p>\n<h3>\u4e09\u3001set\u3001get\u65b9\u6cd5\u4e2d\u7684receiver\u53c2\u6570<\/h3>\n<p>\u5c31\u529f\u80fd\u800c\u8a00\uff0c<code>Reflect.get()<\/code>\u548c<code>Reflect.set()<\/code>\u65b9\u6cd5\u548c\u76f4\u63a5\u5bf9\u8c61\u8d4b\u503c\u6ca1\u6709\u533a\u522b\uff0c\u90fd\u662f\u53ef\u4ee5\u4e92\u76f8\u66ff\u4ee3\u7684\uff0c\u4f8b\u5982\uff0c\u4e0b\u9762\u4e24\u6bb5JS\u6548\u679c\u90fd\u662f\u4e00\u6837\u7684\u3002<\/p>\n<p>\u8fd8\u662f\u4f7f\u7528<code>input<\/code>\u8fd9\u4e2aDOM\u5143\u7d20\u793a\u610f\u3002<\/p>\n<p>\u6709\u4eba\u53ef\u80fd\u4f1a\u7591\u95ee\uff0c\u4e3a\u4ec0\u4e48\u4e0d\u7528\u7eaf\u5bf9\u8c61\u793a\u610f\u5462\uff1f<\/p>\n<p>\u56e0\u4e3a\u6211\u53d1\u73b0\u5927\u591a\u6570\u524d\u7aef\u90fd\u5bf9DOM\u4e0d\u600e\u4e48\u611f\u5174\u8da3\uff0c\u90a3\u6211\u5c31\u53cd\u5176\u9053\u884c\u4e4b\uff0c\u6545\u610f\u8188\u5e94\u4eba <img loading=\"lazy\" decoding=\"async\" src=\"\/\/image.zhangxinxu.com\/image\/emtion\/emoji\/1f92a.svg\" width=\"20\" height=\"20\" align=\"absmiddle\">\uff1b\u53e6\u5916\u4e00\u4e2a\u539f\u56e0\u5c31\u662fDOM\u5bf9\u8c61\u66f4\u5177\u8c61\uff0c\u6240\u89c1\u5373\u6240\u5f97\uff0c\u9002\u5408\u504f\u611f\u6027\u7684\u540c\u5b66\u7684\u5b66\u4e60\u3002<\/p>\n<pre>const xyInput = new Proxy(input, {\r\n    set (target, prop, value) {\r\n        if (prop == 'value') {\r\n            target.dispatchEvent(new CustomEvent('change'));\r\n        }\r\n        target[prop] = value;\r\n\r\n        return true;\r\n    },\r\n    get (target, prop) {\r\n        return target[prop];\r\n    }\r\n});\r\n\r\ninput.addEventListener('change', () => {\r\n  document.body.append('\u53d8\u5316\u5566~');\r\n});\r\nxyInput.value = 'zhangxinxu';<\/pre>\n<p>\u548c\u4e0b\u9762\u7684JS\u4ee3\u7801\u6548\u679c\u7c7b\u4f3c\u7684\u3002<\/p>\n<pre>const xyInput = new Proxy(input, {\r\n    set (target, prop, value) {\r\n        if (prop == 'value') {\r\n            target.dispatchEvent(new CustomEvent('change'));\r\n        }\r\n        return Reflect.set(target, prop, value);\r\n    },\r\n    get (target, prop) {\r\n        return Reflect.get(target, prop);\r\n    }\r\n});\r\n\r\ninput.addEventListener('change', () => {\r\n  document.body.append('\u53d8\u5316\u5566~');\r\n});\r\nxyInput.value = 'zhangxinxu';<\/pre>\n<p>\u5747\u6709\u5982\u4e0b\u56fe\u6240\u793a\u7684\u6548\u679c\uff1a<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202107\/2021-07-01_161934.png\" width=\"254\" height=\"49\" alt=\"Reflect\u4e0evalue\u8d4b\u503c\"><\/p>\n<p>\u4f46\u662f\uff0c\u5f53\u9700\u8981\u4f7f\u7528\u53ef\u9009\u53c2\u6570receiver\u53c2\u6570\u7684\u65f6\u5019\uff0c\u76f4\u63a5\u5bf9\u8c61\u8d4b\u503c\u548c\u4f7f\u7528Reflect\u8d4b\u503c\u5c31\u4f1a\u51fa\u73b0\u5dee\u5f02\u3002<\/p>\n<p>\u9996\u5148\uff0c\u5bf9\u4e8eDOM\u5143\u7d20\uff0c\u5e94\u7528receiver\u53c2\u6570\u4f1a\u62a5\u9519\u3002<\/p>\n<p>\u4f8b\u5982\u4e0b\u9762\u7684JS\u5c31\u4f1a\u62a5\u9519\uff1a<\/p>\n<pre>Reflect.set(input, 'value', 'xxx', new Proxy({}, {}));<\/pre>\n<blockquote><p>Uncaught TypeError: Illegal invocation<\/p><\/blockquote>\n<p>\u4f46\u662f\u628ainput\u6362\u6210\u666e\u901a\u7684\u7eaf\u5bf9\u8c61\uff0c\u5219\u4e0d\u4f1a\u6709\u95ee\u9898\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><span class=\"green\">\/\/ \u53ef\u4ee5\u6b63\u5e38\u6267\u884c<\/span>\r\nReflect.set({}, 'value', 'xxx', new Proxy({}, {}));<\/pre>\n<h4>\u5173\u4e8ereceiver\u53c2\u6570<\/h4>\n<p>\u8bf4\u4e86\u8fd9\u4e48\u591a\uff0c<code>receiver<\/code>\u53c2\u6570\u5230\u5e95\u662f\u5e72\u561b\u7528\u7684\u5462\uff1f<\/p>\n<p>receiver\u662f\u63a5\u53d7\u8005\u7684\u610f\u601d\uff0c\u8868\u793a\u8c03\u7528\u5bf9\u5e94\u5c5e\u6027\u6216\u65b9\u6cd5\u7684\u4e3b\u4f53\u5bf9\u8c61\uff0c\u901a\u5e38\u60c5\u51b5\u4e0b\uff0creceiver\u53c2\u6570\u662f\u65e0\u9700\u4f7f\u7528\u7684\uff0c\u4f46\u662f\u5982\u679c\u53d1\u751f\u4e86\u7ee7\u627f\uff0c\u4e3a\u4e86\u660e\u786e\u8c03\u7528\u4e3b\u4f53\uff0creceiver\u53c2\u6570\u5c31\u9700\u8981\u51fa\u9a6c\u4e86\u3002<\/p>\n<p>\u6bd4\u65b9\u8bf4\u4e0b\u9762\u8fd9\u4e2a\u4f8b\u5b50\uff1a<\/p>\n<pre>let miaoMiao = {\r\n  _name: '\u75ab\u82d7',\r\n  get name () {\r\n    return this._name;\r\n  }\r\n}\r\nlet miaoXy = new Proxy(miaoMiao, {\r\n  get (target, prop, receiver) {\r\n    return target[prop];\r\n  }\r\n});\r\n\r\nlet kexingMiao = {\r\n  __proto__: miaoXy,\r\n  _name: '\u79d1\u5174\u75ab\u82d7'\r\n};\r\n\r\n<span style=\"color:green;\">\/\/ \u7ed3\u679c\u662f\u75ab\u82d7<\/span>\r\nconsole.log(kexingMiao.name);<\/pre>\n<p>\u5b9e\u9645\u4e0a\uff0c\u8fd9\u91cc\u9884\u671f\u663e\u793a\u5e94\u8be5\u662f\u201c\u79d1\u5174\u75ab\u82d7\u201d\uff0c\u800c\u4e0d\u662f\u201c\u75ab\u82d7\u201d\u3002<\/p>\n<p>\u8fd9\u4e2a\u65f6\u5019\uff0c\u5c31\u9700\u8981\u4f7f\u7528<code>receiver<\/code>\u53c2\u6570\u4e86\uff0c\u4ee3\u7801\u53d8\u5316\u90e8\u5206\u53c2\u89c1\u4e0b\u9762\u6807\u7ea2\u7684\u90a3\u4e00\u884c\uff1a<\/p>\n<pre>let miaoMiao = {\r\n  _name: '\u75ab\u82d7',\r\n  get name () {\r\n    return this._name;\r\n  }\r\n}\r\nlet miaoXy = new Proxy(miaoMiao, {\r\n  get (target, prop, receiver) {\r\n    <span style=\"color:#cd0000;\">return Reflect.get(target, prop, receiver);<\/span>\r\n    <span style=\"color:green;\">\/\/ \u4e5f\u53ef\u4ee5\u7b80\u5199\u4e3a Reflect.get(...arguments) <\/span>\r\n  }\r\n});\r\n\r\nlet kexingMiao = {\r\n  __proto__: miaoXy,\r\n  _name: '\u79d1\u5174\u75ab\u82d7'\r\n};\r\n\r\n<span style=\"color:green;\">\/\/ \u7ed3\u679c\u662f\u79d1\u5174\u75ab\u82d7 <img loading=\"lazy\" decoding=\"async\" src=\"\/\/image.zhangxinxu.com\/image\/emtion\/emoji\/270c.svg\" width=\"20\" height=\"20\" align=\"absmiddle\"><\/span>\r\nconsole.log(kexingMiao.name);<\/pre>\n<p>\u6b64\u65f6\uff0c\u8fd0\u884c\u7ed3\u679c\u5c31\u662f\u9884\u671f\u7684\u201c\u79d1\u5174\u75ab\u82d7\u201d\u4e86\uff0c\u5982\u4e0b\u622a\u56fe\u6240\u793a\uff1a<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202107\/2021-07-01_223705.png\" width=\"364\" height=\"390\" alt=\"\u79d1\u5174\u75ab\u82d7\" class=\"alignnone size-medium\" \/><\/p>\n<p>\u8fd9\u5c31\u662freceiver\u53c2\u6570\u7684\u4f5c\u7528\uff0c\u53ef\u4ee5\u628a\u8c03\u7528\u5bf9\u8c61\u5f53\u4f5ctarget\u53c2\u6570\uff0c\u800c\u4e0d\u662f\u539f\u59cbProxy\u6784\u9020\u7684\u5bf9\u8c61\u3002<\/p>\n<h3>\u56db\u3001\u5176\u4ed6\u4ee5\u53ca\u7ed3\u675f\u8bed<\/h3>\n<p>Reflect\u5bf9\u8c61\u7ecf\u5e38\u548cProxy\u4ee3\u7406\u4e00\u8d77\u4f7f\u7528\uff0c\u539f\u56e0\u6709\u4e09\u70b9\uff1a<\/p>\n<ol>\n<li>Reflect\u63d0\u4f9b\u7684\u6240\u6709\u9759\u6001\u65b9\u6cd5\u548cProxy\u7b2c2\u4e2ahandle\u53c2\u6570\u65b9\u6cd5\u662f\u4e00\u6a21\u4e00\u6837\u7684\u3002\u5177\u4f53\u89c1\u540e\u9762\u7684\u5bf9\u6bd4\u63cf\u8ff0\u3002<\/li>\n<li>Proxy get\/set()\u65b9\u6cd5\u9700\u8981\u7684\u8fd4\u56de\u503c\u6b63\u662fReflect\u7684get\/set\u65b9\u6cd5\u7684\u8fd4\u56de\u503c\uff0c\u53ef\u4ee5\u5929\u7136\u914d\u5408\u4f7f\u7528\uff0c\u6bd4\u76f4\u63a5\u5bf9\u8c61\u8d4b\u503c\/\u83b7\u53d6\u503c\u8981\u66f4\u65b9\u4fbf\u548c\u51c6\u786e\u3002<\/li>\n<li>receiver\u53c2\u6570\u5177\u6709\u4e0d\u53ef\u66ff\u4ee3\u6027\u3002<\/li>\n<\/ol>\n<p>\u4e0b\u8868\u662f\u81ea\u5df1\u6574\u7406\u7684Reflect\u9759\u6001\u65b9\u6cd5\u548c\u5bf9\u5e94\u7684\u5176\u4ed6\u51fd\u6570\u6216\u529f\u80fd\u7b26\u3002<\/p>\n<table border=\"0\" width=\"100%\" class=\"params_table\" cellspacing=\"1\">\n<thead>\n<tr>\n<th>Reflect\u65b9\u6cd5<\/th>\n<th>\u7c7b\u4f3c\u4e8e<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Reflect.apply(target, thisArgument, argumentsList)<\/td>\n<td>Function.prototype.apply()<\/td>\n<\/tr>\n<tr>\n<td>Reflect.construct(target, argumentsList[, newTarget])<\/td>\n<td>new target(&#8230;args)<\/td>\n<\/tr>\n<tr>\n<td>Reflect.defineProperty(target, prop, attributes)<\/td>\n<td>Object.defineProperty() <\/td>\n<\/tr>\n<tr>\n<td>Reflect.deleteProperty(target, prop)<\/td>\n<td>delete target[name]<\/td>\n<\/tr>\n<tr>\n<td>Reflect.get(target, prop[, receiver])<\/td>\n<td>target[name]<\/td>\n<\/tr>\n<tr>\n<td>Reflect.getOwnPropertyDescriptor(target, prop)<\/td>\n<td>Object.getOwnPropertyDescriptor()<\/td>\n<\/tr>\n<tr>\n<td>Reflect.getPrototypeOf(target)<\/td>\n<td>Object.getPrototypeOf()<\/td>\n<\/tr>\n<tr>\n<td>Reflect.has(target, prop)<\/td>\n<td>in \u8fd0\u7b97\u7b26<\/td>\n<\/tr>\n<tr>\n<td>Reflect.isExtensible(target)<\/td>\n<td>Object.isExtensible()<\/td>\n<\/tr>\n<tr>\n<td>Reflect.ownKeys(target)<\/td>\n<td>Object.keys()<\/td>\n<\/tr>\n<tr>\n<td>Reflect.preventExtensions(target)<\/td>\n<td>Object.preventExtensions()<\/td>\n<\/tr>\n<tr>\n<td>Reflect.set(target, prop, value[, receiver])<\/td>\n<td>target[prop] = value<\/td>\n<\/tr>\n<tr>\n<td>Reflect.setPrototypeOf(target, prototype)<\/td>\n<td>Object.setPrototypeOf()<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u6b63\u662f\u4eba\u5982\u5176\u540d\uff0cReflect\u5c31\u662f\u5176\u4ed6\u65b9\u6cd5\u3001\u64cd\u4f5c\u7b26\u7684\u201c\u53cd\u5c04\u201d\u3002<\/p>\n<p>\u597d\uff0c\u4ee5\u4e0a\u5c31\u662f\u672c\u6587\u7684\u5185\u5bb9\uff0c\u5e26\u5927\u5bb6\u4e86\u89e3\u4e86\u4e0bReflect\u7684\u4e03\u4e03\u516b\u516b\u3002<\/p>\n<p>\u5e0c\u671b\u53ef\u4ee5\u5bf9\u5927\u5bb6\u7684\u5b66\u4e60\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n<p>\u6b22\u8fce\u8f6c\u53d1\uff0c\u6b22\u8fce\u5206\u4eab\uff0c\u8c22\u8c22\u8c22\u8c22\uff01<\/p>\n<p><strong>\u53c2\u8003\u6587\u6863<\/strong><\/p>\n<ul>\n<li><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/JavaScript\/Reference\/Global_Objects\/Reflect\" rel=\"noopener nofollow\" target=\"_blank\">MDN Reflect<\/a><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"\/\/image.zhangxinxu.com\/image\/emtion\/emoji\/1f618.svg\" width=\"20\" height=\"20\" align=\"absmiddle\"><\/p>\n<p>\u672c\u6587\u4e3a\u539f\u521b\u6587\u7ae0\uff0c\u6b22\u8fce\u5206\u4eab\uff0c\u52ff\u5168\u6587\u8f6c\u8f7d\uff0c\u5982\u679c\u5b9e\u5728\u559c\u6b22\uff0c\u53ef\u6536\u85cf\uff0c\u6c38\u4e0d\u8fc7\u671f\uff0c\u4e14\u4f1a\u53ca\u65f6\u66f4\u65b0\u77e5\u8bc6\u70b9\u53ca\u4fee\u6b63\u9519\u8bef\uff0c\u9605\u8bfb\u4f53\u9a8c\u4e5f\u66f4\u597d\u3002<br \/>\n\u672c\u6587\u5730\u5740\uff1a<a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/?p=9984\">https:\/\/www.zhangxinxu.com\/wordpress\/?p=9984<\/a><\/p>\n<p>\uff08\u672c\u7bc7\u5b8c\uff09<\/p>\n","protected":false},"excerpt":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202107\/reflect-cover.jpg\" width=\"160\" height=\"103\" alt=\"\u5c01\u9762\u56fe\u793a\u610f\" class=\"alignright size-medium\" loading=\"lazy\" \/><\/p>\n<p>\u672c\u6587\u8be6\u7ec6\u4ecb\u7ecdJS\u4e2d\u7684Reflect\u5bf9\u8c61\uff0c\u4e0eProxy\u4ee3\u7406\u4e4b\u95f4\u7684\u5173\u7cfb\uff0c\u5185\u5bb9\u8be6\u5b9e\uff0c\u5e94\u8be5\u53ef\u4ee5\u5b66\u5230\u70b9\u4e1c\u897f\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1284],"tags":[1767,1474,1768,904,1755,1766,1237,775,1757,1765],"_links":{"self":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/9984"}],"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=9984"}],"version-history":[{"count":0,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/9984\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/media?parent=9984"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/categories?post=9984"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/tags?post=9984"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}