{"id":6102,"date":"2020-05-07T19:36:57","date_gmt":"2020-05-07T11:36:57","guid":{"rendered":"https:\/\/www.lilichao.com\/?p=6102"},"modified":"2022-05-14T19:40:37","modified_gmt":"2022-05-14T11:40:37","slug":"js%e6%8a%8a%e5%8f%98%e9%87%8f%e5%ad%98%e5%93%aa%e4%ba%86%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/lilichao.com\/?p=6102","title":{"rendered":"JS\u628a\u53d8\u91cf\u5b58\u54ea\u4e86\uff1f"},"content":{"rendered":"\n<p>\u5728JS\u4e2d\u53d8\u91cf\u662f\u7528\u6765\u5b58\u50a8\u5bf9\u8c61\u7684\uff0c\u4f46\u53d8\u91cf\u4e5f\u5c5e\u4e8e\u7a0b\u5e8f\u4e2d\u7684\u4e00\u90e8\u5206\uff0c\u4e5f\u8981\u5b58\u50a8\u5230\u5185\u5b58\u4e4b\u4e2d\uff0c\u90a3\u4e48\u5c31\u4ea7\u751f\u4e86\u4e00\u4e2a\u95ee\u9898\uff0c\u53d8\u91cf\u5b58\u50a8\u5728\u54ea\u91cc\u5462\uff1f<\/p>\n\n\n\n<p>\u8fd9\u4e00\u70b9\u6211\u4eec\u4e4b\u524d\u66fe\u7ecf\u63d0\u5230\u8fc7\uff0c\u53d8\u91cf\u88ab\u5b58\u50a8\u5230\u4e00\u4e2a\u540d\u4e3a\u201c\u53d8\u91cf\u5bf9\u8c61\u201d\u7684\u5bf9\u8c61\u4e2d\u3002\u6240\u8c13\u7684\u521b\u5efa\u53d8\u91cf\u5176\u5b9e\u5c31\u662f\u5411\u201c\u53d8\u91cf\u5bf9\u8c61\u201d\u4e2d\u6dfb\u52a0\u5c5e\u6027\u3002\u90a3\u4e48\u53d8\u91cf\u5bf9\u8c61\u662f\u4ec0\u4e48\u6837\u5b50\u5462\uff1f\u6211\u4eec\u80fd\u5426\u770b\u5230\u5462\uff1f\u5176\u5b9e\u901a\u8fc7\u4e00\u4e9b\u5de5\u5177\u6211\u4eec\u662f\u53ef\u4ee5\u770b\u5230\u53d8\u91cf\u5bf9\u8c61\u7684\u3002\u4e3e\u4e2a\u4f8b\u5b50\uff0c\u6709\u5982\u4e0bjs\u4ee3\u7801\uff0c\u5199\u5728\u4e86index.html\u6587\u4ef6\u4e2d\u3002<\/p>\n\n\n\n<div 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src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193845777.png\" alt=\"\" class=\"wp-image-6105\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193845777.png 1024w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193845777-300x105.png 300w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193845777-768x270.png 768w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193845777-1000x352.png 1000w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" 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height=\"368\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193900443.png\" alt=\"\" class=\"wp-image-6107\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193900443.png 874w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193900443-300x126.png 300w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193900443-768x323.png 768w\" sizes=\"(max-width: 874px) 100vw, 874px\" \/><figcaption>\u4ee3\u7801\u505c\u6b62\u5728\u7b2c7\u884c<\/figcaption><\/figure><\/div>\n\n\n\n<p>\u4ee3\u7801\u73b0\u5728\u505c\u6b62\u5728\u4e86\u7b2c7\u884c\u7684\u4f4d\u7f6e\uff08\u7b2c7\u884c\u8fd8\u6ca1\u8fd0\u884c\uff09\uff0c\u73b0\u5728\u6211\u4eec\u5c31\u53ef\u4ee5\u67e5\u770b\u53f3\u4fa7\u7684\u5173\u4e8e\u4ee3\u7801\u7684\u8fd0\u884c\u7ec6\u8282\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"228\" height=\"319\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193908945.png\" alt=\"\" class=\"wp-image-6108\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193908945.png 228w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193908945-214x300.png 214w\" sizes=\"(max-width: 228px) 100vw, 228px\" \/><\/figure><\/div>\n\n\n\n<p>\u53f3\u4fa7\u7684\u4e1c\u897f\u633a\u591a\u7684\uff0c\u6211\u4eec\u5148\u770b\u91cd\u8981\u7684\u4e1c\u897f\u3002\u53f3\u4fa7\u6709\u4e00\u4e2a\u6807\u7b7e\u53eb\u505aScope\uff0cScope\u8868\u793a\u533a\u57df\uff0c\u53ef\u4ee5\u76f4\u63a5\u7406\u89e3\u4e3a\u4f5c\u7528\u57df\u3002\u6807\u7b7e\u9ed8\u8ba4\u662f\u53e0\u8d77\u6765\u7684\uff0c\u53ef\u4ee5\u5355\u51fb\u67e5\u770b\u7ec6\u8282\u3002\u5728Scope\u4e2d\u663e\u793a\u7684\u5c31\u662f\u201c\u4f20\u8bf4\u4e2d\u201d\u7684\u53d8\u91cf\u5bf9\u8c61\u3002<\/p>\n\n\n\n<p>\u73b0\u5728\u80fd\u770b\u5230\u7684\u4e00\u4e2a\u53d8\u91cf\u5bf9\u8c61\u53eb\u505aGlobal\uff0cGlobal\u8868\u793a\u5168\u7403\u7684\u5168\u5c40\u7684\u3002\u6240\u4ee5\u8fd9\u4e2a\u4e1c\u897f\u6211\u4eec\u4e5f\u53eb\u505a\u5168\u5c40\u5bf9\u8c61\u3002\u5728\u6d4f\u89c8\u5668\u4e2d\u5168\u5c40\u5bf9\u8c61\u7684\u540d\u5b57\u53eb\u505awindow\u6216globalThis\u3002\u5168\u5c40\u5bf9\u8c61\u5f88\u7279\u6b8a\uff0c\u5b83\u662fJS\u4e2d\u7684\u6839\u5bf9\u8c61\uff0cJS\u4e2d\u7684\u6240\u6709\u4e00\u5207\u90fd\u5b58\u50a8\u5728\u5b83\u7684\u91cc\u8fb9\u3002<\/p>\n\n\n\n<p>\u50cf\u662falert\u3001console\u8fd9\u4e9b\u5bf9\u8c61\u5b9e\u9645\u90fd\u662f\u5168\u5c40\u5bf9\u8c61\u7684\u5c5e\u6027\u3002\u4e0b\u5217\u4e09\u4e2a\u8c03\u7528\u672c\u8d28\u4e0a\u662f\u4e00\u6837\u7684\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><em><code>alert<\/code><\/em><code>(123)\nwindow.alert(123)\nglobalThis.<\/code><em><code>alert<\/code><\/em><code>(123)<\/code><\/pre>\n\n\n\n<p>\u6240\u4ee5\u53ef\u4ee5\u8fd9\u4e48\u7406\u89e3\uff0c\u5168\u5c40\u5bf9\u8c61\u7684\u5c5e\u6027\u90fd\u5c5e\u4e8e\u5168\u5c40\u53d8\u91cf\u3002\u4f46\u8fd9\u53e5\u8bdd\u5e76\u4e0d\u610f\u5473\u7740\u6240\u6709\u7684\u5168\u5c40\u53d8\u91cf\u90fd\u4f1a\u5b58\u50a8\u5728\u5168\u5c40\u5bf9\u8c61\u4e2d\u3002\u73b0\u5728\u53ef\u4ee5\u8ba9\u4ee3\u7801\u5411\u4e0b\u6267\u884c\u4e00\u4e0b\uff0c\u70b9\u51fb\u53f3\u4fa7\u7b2c\u4e00\u884c\u7b2c\u4e8c\u4e2a\u56fe\u6807\uff0c\u4f7f\u4ee3\u7801\u5411\u4e0b\u6267\u884c\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"872\" height=\"372\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193915280.png\" alt=\"\" class=\"wp-image-6109\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193915280.png 872w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193915280-300x128.png 300w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193915280-768x328.png 768w\" sizes=\"(max-width: 872px) 100vw, 872px\" \/><figcaption>\u5411\u4e0b\u6267\u884c\u4ee3\u7801<\/figcaption><\/figure>\n\n\n\n<p>\u70b9\u51fb\u6309\u94ae\u540e\uff0c\u4ee3\u7801\u4f1a\u5411\u4e0b\u6267\u884c\u4e00\u884c\uff0c\u4e5f\u5c31\u662f\u6267\u884c\u7b2c7\u884c\uff0c\u7b2c7\u884c\u4ee3\u7801\u6267\u884c\u5b8c\u6bd5\u3002\u5b83\u7684\u4f5c\u7528\u662f\u521b\u5efa\u4e00\u4e2a\u5168\u5c40\u53d8\u91cfa\u5e76\u8d4b\u503c\u4e3a10\u3002\u6ce8\u610f\u4ee3\u7801\u6267\u884c\u5b8c\u6bd5\u540e\uff0c\u53f3\u4fa7Scope\u6807\u7b7e\u4e0b\u591a\u51fa\u4e86\u4e00\u4e2aScript\u5bf9\u8c61\uff0c\u55ef\uff0c\u6ca1\u9519\uff0c\u8fd9\u5c31\u662f\u5168\u5c40\u53d8\u91cf\u5bf9\u8c61\u3002\u4f7f\u7528let\u58f0\u660e\u7684\u53d8\u91cf\u5168\u90fd\u5b58\u50a8\u5728\u8be5\u5bf9\u8c61\u4e2d\uff0c\u8fd9\u4e2a\u5bf9\u8c61\u6211\u4eec\u6ca1\u6709\u529e\u6cd5\u76f4\u63a5\u8bbf\u95ee\uff0c\u53ea\u80fd\u901a\u8fc7\u5de5\u5177\u67e5\u770b\u3002\u73b0\u5728\u53ef\u4ee5\u5c1d\u8bd5\u591a\u58f0\u660e\u51e0\u4e2a\u53d8\u91cf\uff0c\u518d\u6765\u67e5\u770b\u4e00\u4e0b\u5b83\u7684\u7ed3\u6784\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"633\" height=\"335\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193922330.png\" alt=\"\" class=\"wp-image-6110\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193922330.png 633w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193922330-300x159.png 300w\" sizes=\"(max-width: 633px) 100vw, 633px\" \/><figcaption>\u591a\u58f0\u660e\u51e0\u4e2a\u53d8\u91cf<\/figcaption><\/figure><\/div>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"212\" height=\"106\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193930818.png\" alt=\"\" class=\"wp-image-6111\"\/><figcaption>\u67e5\u770b\u53d8\u91cf\u5bf9\u8c61<\/figcaption><\/figure><\/div>\n\n\n\n<p>\u53d1\u73b0\u6240\u6709\u7684\u53d8\u91cf\u90fd\u5728Script\u5bf9\u8c61\u4e2d\uff08\u6ca1\u6709\u53d8\u91cf\u7684\uff0c\u56e0\u4e3a\u7b2c10\u884c\u4ee3\u7801\u8fd8\u6ca1\u6709\u6267\u884c\uff09\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u7279\u6b8a\u60c5\u51b5<\/h2>\n\n\n\n<p>\u5982\u679c\u4f7f\u7528var\u5173\u952e\u5b57\u58f0\u660e\u5168\u5c40\u53d8\u91cf\uff0c\u53d8\u91cf\u4f1a\u76f4\u63a5\u6dfb\u52a0\u5230\u5168\u5c40\u5bf9\u8c61\uff08window\uff09\u4e2d\uff0c\u4e0d\u4f1a\u5355\u72ec\u521b\u5efaScript\u53d8\u91cf\u5bf9\u8c61\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"866\" height=\"322\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193938572.png\" alt=\"\" class=\"wp-image-6112\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193938572.png 866w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193938572-300x112.png 300w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193938572-768x286.png 768w\" sizes=\"(max-width: 866px) 100vw, 866px\" \/><figcaption>\u4f7f\u7528var\u58f0\u660e\u7684\u5168\u5c40\u53d8\u91cf\u4e0d\u4f1a\u521b\u5efaScript\u53d8\u91cf\u5bf9\u8c61<\/figcaption><\/figure>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"220\" height=\"222\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193945884.png\" alt=\"\" class=\"wp-image-6113\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193945884.png 220w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193945884-150x150.png 150w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193945884-120x120.png 120w\" sizes=\"(max-width: 220px) 100vw, 220px\" \/><figcaption>\u5728global\u4e2d\u627e\u5230\u4e86\u53d8\u91cfa\u548cb<\/figcaption><\/figure><\/div>\n\n\n\n<p>\u4f7f\u7528\u8d77\u6765\u533a\u522b\u4e0d\u5927\uff0c\u4f46\u662f\u4f7f\u7528\u65f6\u8fd8\u662f\u6709\u4e00\u4e9b\u5730\u65b9\u6bd4\u8f83\u5bb9\u6613\u51fa\u95ee\u9898\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><code>var a = 10\nconsole.log(window.a) \/\/ 10\nconsole.log(globalThis.a) \/\/ 10<\/code><\/pre>\n\n\n\n<p>var\u58f0\u660e\u7684\u53d8\u91cf\u4f1a\u6210\u4e3awindow\u5bf9\u8c61\u7684\u5c5e\u6027\u6240\u4ee5\u4e0a\u8fb9\u90a3\u4e48\u5199\u4e00\u70b9\u95ee\u9898\u4e5f\u6ca1\u6709\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><code>let a = 10\nconsole.log(window.a) <\/code><em><code>\/\/ undefined\n<\/code><\/em><code>console.log(globalThis.a) <\/code><em><code>\/\/ undefined<\/code><\/em><\/pre>\n\n\n\n<p>let\u58f0\u660e\u7684\u53d8\u91cf\u4e0d\u4f1a\u5b58\u50a8\u5230window\u5bf9\u8c61\u4e2d\uff0c\u4f7f\u7528\u65f6\u4f1a\u6253\u5370undefined<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">var\u7684\u63d0\u524d\u58f0\u660e<\/h3>\n\n\n\n<p>\u9664\u6b64\u4e4b\u5916\uff0cvar\u58f0\u660e\u7684\u53d8\u91cf\u8fd8\u6709\u4e00\u4e2a\u7279\u70b9\uff0c\u5b83\u4f1a\u5728\u6240\u6709\u7684\u4ee3\u7801\u6267\u884c\u524d\u88ab\u58f0\u660e\u3002\u6bd4\u5982\u6709\u5982\u4e0b\u4ee3\u7801<code>var a = 10<\/code>\uff0c\u53d8\u91cf\u7684\u58f0\u660e\u4e5f\u5c31\u662f<code>var a<\/code>\u4f1a\u4f18\u5148\u6267\u884c\uff0c\u901a\u8fc7\u5f00\u53d1\u8005\u5de5\u5177\u4f60\u4f1a\u53d1\u73b0\u4ee3\u7801\u8fd8\u6ca1\u6267\u884c\uff0c\u4f46\u662f\u5728window\u5bf9\u8c61\u4e2d\u5df2\u7ecf\u5177\u6709\u4e86a\u8fd9\u4e2a\u5c5e\u6027\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"866\" height=\"365\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193954264.png\" alt=\"\" class=\"wp-image-6114\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193954264.png 866w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193954264-300x126.png 300w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514193954264-768x324.png 768w\" sizes=\"(max-width: 866px) 100vw, 866px\" \/><figcaption>a\u88ab\u63d0\u524d\u58f0\u660e\u4e86<\/figcaption><\/figure><\/div>\n\n\n\n<p>\u4e0a\u4f8b\u4e2d\uff0c\u7b2c7\u884c\u4ee3\u7801\u8fd8\u672a\u6267\u884c\uff0c\u4f46\u662f\u5728\u5168\u5c40\u5bf9\u8c61\u4e2d\u5df2\u7ecf\u51fa\u73b0\u4e86a\u8fd9\u4e2a\u5c5e\u6027\u3002\u8fd9\u5c31\u662f\u6240\u8c13\u7684\u63d0\u524d\u58f0\u660e\uff0c\u4e5f\u53ef\u4ee5\u79f0\u4e3a\u53d8\u91cf\u7684\u63d0\u5347\u3002\u4f46\u662f\u6b64\u65f6a\u7684\u503c\u8fd8\u662fundefined\uff0c\u8fd9\u662f\u56e0\u4e3a\u53ea\u4f1a\u63d0\u524d\u58f0\u660e\u5e76\u4e0d\u4f1a\u63d0\u524d\u8d4b\u503c\u3002<\/p>\n\n\n\n<p>\u770b\u5230\u8fd9\u91cc\u4f60\u4f1a\u89c9\u5f97\u5f88\u5947\u602a\uff0c\u8fd9\u662f\u4ec0\u4e48\u5957\u8def\u3002var\u5173\u952e\u5b57\u672c\u8eab\u5c31\u662fJS\u65e9\u671f\u7684\u4ea7\u7269\uff0c\u5e76\u4e0d\u6210\u719f\uff0c\u6240\u4ee5\u5b58\u5728\u6709\u5f88\u591a\u7684\u9057\u7559\u95ee\u9898\uff0c\u5173\u4e8evar\u7684\u7279\u70b9\u8be5\u4e86\u89e3\u8fd8\u662f\u8981\u4e86\u89e3\u7684\uff0c\u4f46\u662f\u5f00\u53d1\u4e2d\u5c3d\u91cf\u4e0d\u8981\u53bb\u4f7f\u7528var\u5173\u952e\u5b57\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u51fd\u6570\u7684\u63d0\u5347<\/h3>\n\n\n\n<p>\u9664\u4e86var\u58f0\u660e\u7684\u53d8\u91cf\u5916\uff0c\u5168\u5c40\u4e2d\u4f7f\u7528function\u5f00\u5934\u7684\u51fd\u6570\u4e5f\u4f1a\u4f5c\u4e3awindow\u5bf9\u8c61\u7684\u5c5e\u6027\u4fdd\u5b58\uff0c\u540c\u65f6\u4e5f\u4f1a\u88ab\u63d0\u5347\uff0c\u5e76\u4e14\u51fd\u6570\u7684\u63d0\u5347\u4e0d\u4ec5\u4ec5\u662f\u63d0\u524d\u58f0\u660e\uff0c\u6240\u6709\u4f7f\u7528function\u5f00\u5934\u7684\u51fd\u6570\u4f1a\u5728\u6240\u6709\u7684\u4ee3\u7801\u6267\u884c\u524d\u88ab\u521b\u5efa\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"874\" height=\"345\" src=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514194000243.png\" alt=\"\" class=\"wp-image-6115\" srcset=\"https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514194000243.png 874w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514194000243-300x118.png 300w, https:\/\/my-wp.oss-cn-beijing.aliyuncs.com\/wp-content\/uploads\/2022\/05\/20220514194000243-768x303.png 768w\" sizes=\"(max-width: 874px) 100vw, 874px\" \/><\/figure><\/div>\n\n\n\n<p>\u5bf9\u4e8e\u51fd\u6570\u6765\u8bf4\uff0c\u53ef\u4ee5\u5728\u51fd\u6570\u521b\u5efa\u524d\u5bf9\u5176\u8fdb\u884c\u8c03\u7528\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><em><code>fn<\/code><\/em><code>()\n function <\/code><em><code>fn<\/code><\/em><code>() {\n &nbsp; &nbsp; console.log('\u6211\u662ffn\u51fd\u6570')\n}<\/code><\/pre>\n\n\n\n<p>\u4e0a\u8fb9\u8fd9\u4e48\u5199\uff0c\u4e00\u70b9\u95ee\u9898\u90fd\u6ca1\u6709\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><em><code>fn<\/code><\/em><code>()<\/code><em><code>\/\/ \u51fd\u6570\u6ca1\u6709\u4ee5function\u5f00\u5934\uff0c\u4e0d\u4f1a\u63d0\u5347\uff0c\u8fd9\u91cc\u4f1a\u62a5\u9519<\/code><\/em><code> \nlet <\/code><em><code>fn <\/code><\/em><code>= function () {\n &nbsp; &nbsp; console.log('\u6211\u662ffn\u51fd\u6570')\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-preformatted\"><em><code>fn<\/code><\/em><code>() <\/code><em><code>\/\/ \u51fd\u6570\u6ca1\u6709\u4ee5function\u5f00\u5934\uff0c\u4e0d\u4f1a\u63d0\u5347\uff0c\u8fd9\u91cc\u4f1a\u62a5\u9519\n<\/code><\/em><code>var <\/code><em><code>fn <\/code><\/em><code>= function () {\n&nbsp; &nbsp; console.log('\u6211\u662ffn\u51fd\u6570')\n}<\/code><\/pre>\n\n\n\n<p>\u4f7f\u7528let\u548cvar\u521b\u5efa\u51fd\u6570\uff0c\u4e0d\u4f1a\u88ab\u63d0\u5347\uff08var\u53ea\u4f1a\u63d0\u5347\u53d8\u91cf\u7684\u58f0\u660e\uff0c\u4e0d\u4f1a\u63d0\u5347\u51fd\u6570\u7684\u521b\u5efa\uff09\u3002\u6240\u4ee5\u5728\u51fd\u6570\u58f0\u660e\u524d\u8c03\u7528\u65f6\u4f1a\u62a5\u9519\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728JS\u4e2d\u53d8\u91cf\u662f\u7528\u6765\u5b58\u50a8\u5bf9\u8c61\u7684\uff0c\u4f46\u53d8\u91cf\u4e5f\u5c5e\u4e8e\u7a0b\u5e8f\u4e2d\u7684\u4e00\u90e8\u5206\uff0c\u4e5f\u8981\u5b58\u50a8\u5230\u5185\u5b58\u4e4b\u4e2d\uff0c\u90a3\u4e48\u5c31\u4ea7\u751f\u4e86\u4e00\u4e2a\u95ee\u9898\uff0c\u53d8\u91cf\u5b58\u50a8\u5728 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