{"id":3742,"date":"2024-11-10T12:42:17","date_gmt":"2024-11-10T04:42:17","guid":{"rendered":"https:\/\/fwq.ai\/blog\/3742\/"},"modified":"2024-11-10T12:42:17","modified_gmt":"2024-11-10T04:42:17","slug":"es6-%e4%b8%ad-const-%e5%92%8c-let-%e7%9a%84%e5%8c%ba%e5%88%ab%ef%bc%9a%e4%b8%ba%e4%bb%80%e4%b9%88%e5%8f%af%e4%bb%a5%e9%87%8d%e6%96%b0%e8%b5%8b%e5%80%bc-const-%e5%ae%9a%e4%b9%89%e7%9a%84%e5%8f%98","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/3742\/","title":{"rendered":"ES6 \u4e2d const \u548c let \u7684\u533a\u522b\uff1a\u4e3a\u4ec0\u4e48\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c const \u5b9a\u4e49\u7684\u53d8\u91cf\uff1f"},"content":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/001\/246\/273\/173112930358898.jpg\" class=\"aligncenter\" title=\"ES6 \u4e2d const \u548c let \u7684\u533a\u522b\uff1a\u4e3a\u4ec0\u4e48\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c const \u5b9a\u4e49\u7684\u53d8\u91cf\uff1f\u63d2\u56fe\" alt=\"ES6 \u4e2d const \u548c let \u7684\u533a\u522b\uff1a\u4e3a\u4ec0\u4e48\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c const \u5b9a\u4e49\u7684\u53d8\u91cf\uff1f\u63d2\u56fe\" \/><\/p>\n<p><strong>ES6\u4e2dconst\u548clet\u7684<\/strong><\/p>\n<p>\u5728ES6\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528const\u5173\u952e\u5b57\u5b9a\u4e49\u5e38\u91cf\uff0c\u8be5\u5e38\u91cf\u4e00\u65e6\u5b9a\u4e49\u540e\u4e0d\u80fd\u88ab\u91cd\u65b0\u8d4b\u503c\u3002\u800c\u5728\u4e0a\u8ff0\u4ee3\u7801\u793a\u4f8b\u4e2d\uff0c\u867d\u7136\u5df2\u7ecf\u4f7f\u7528const\u5b9a\u4e49\u4e86\u5e38\u91cfPI\uff0c\u4f46\u540e\u9762\u4f7f\u7528let PI\u91cd\u65b0\u8d4b\u503c\uff0c\u5374\u4e0d\u4f1a\u62a5\u9519\u3002<\/p>\n<p>\u8fd9\u662f\u56e0\u4e3alet\u548cconst\u5728\u5b9a\u4e49\u53d8\u91cf\u65f6\u7684\u4e0d\u540c\u884c\u4e3a\u5bfc\u81f4\u7684\uff1a<\/p>\n<ul>\n<li> <strong>let:<\/strong> \u5b9a\u4e49let\u53d8\u91cf\u540e\uff0c\u5728\u4f7f\u7528\u524d\u5fc5\u987b\u5bf9\u5176\u521d\u59cb\u5316\uff0c\u5426\u5219\u4f1a\u5bfc\u81f4\u5f15\u7528\u9519\u8bef\u3002<\/li>\n<li> <strong>const:<\/strong> \u5b9a\u4e49const\u53d8\u91cf\u540e\uff0c\u5fc5\u987b\u5bf9\u5176\u521d\u59cb\u5316\uff0c\u5e76\u4e14\u4e0d\u80fd\u5728\u4e4b\u540e\u91cd\u65b0\u8d4b\u503c\u3002<\/li>\n<\/ul>\n<p>\u5728\u4e0a\u8ff0\u793a\u4f8b\u4e2d\uff0c\u7531\u4e8elet PI\u662f\u5728const PI\u4e4b\u540e\u5b9a\u4e49\u7684\uff0c\u56e0\u6b64\u5728\u4f7f\u7528\u524d\u5fc5\u987b\u5bf9\u5176\u521d\u59cb\u5316\u3002\u7531\u4e8elet\u53d8\u91cf\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c\uff0c\u56e0\u6b64\u4e0a\u65b9\u7684\u4ee3\u7801\u4e0d\u4f1a\u62a5\u9519\uff0c\u5e76\u6210\u529f\u5c06PI\u8d4b\u503c\u4e3a&#8221;2222&#8243;\u3002<\/p>\n<p>\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0cconst\u5e76\u4e0d\u662f\u771f\u6b63\u610f\u4e49\u4e0a\u7684\u5e38\u91cf\uff0c\u5b83\u5b9e\u9645\u4e0a\u662f\u4e00\u79cd\u5f15\u7528\u7c7b\u578b\u3002\u5bf9\u4e8e\u5f15\u7528\u7c7b\u578b\uff0c\u6211\u4eec\u65e0\u6cd5\u6539\u53d8\u5176\u5f15\u7528\u5730\u5740\uff0c\u4f46\u53ef\u4ee5\u6539\u53d8\u5176\u5185\u90e8\u6570\u636e\u3002\u56e0\u6b64\uff0c\u5728\u4f7f\u7528const\u5b9a\u4e49\u5bf9\u8c61\u6216\u6570\u7ec4\u65f6\uff0c\u53ef\u4ee5\u4fee\u6539\u5176\u5185\u90e8\u6570\u636e\uff0c\u4f46\u65e0\u6cd5\u91cd\u65b0\u8d4b\u503c\u6574\u4e2a\u5bf9\u8c61\u6216\u6570\u7ec4\u3002<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fES6 \u4e2d const \u548c let \u7684\uff1a\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c const \u5b9a\u4e49\u7684\u53d8\u91cf\uff1f\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>ES6\u4e2dconst\u548clet\u7684 \u5728ES6\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528const\u5173\u952e\u5b57\u5b9a\u4e49\u5e38\u91cf\uff0c\u8be5\u5e38\u91cf\u4e00\u65e6\u5b9a\u4e49\u540e\u4e0d\u80fd\u88ab\u91cd\u65b0\u8d4b\u503c\u3002\u800c\u5728\u4e0a\u8ff0\u4ee3\u7801\u793a\u4f8b\u4e2d\uff0c\u867d\u7136\u5df2\u7ecf\u4f7f\u7528const\u5b9a\u4e49\u4e86\u5e38\u91cfPI\uff0c\u4f46\u540e\u9762\u4f7f\u7528let PI\u91cd\u65b0\u8d4b\u503c\uff0c\u5374\u4e0d\u4f1a\u62a5\u9519\u3002 \u8fd9\u662f\u56e0\u4e3alet\u548cconst\u5728\u5b9a\u4e49\u53d8\u91cf\u65f6\u7684\u4e0d\u540c\u884c\u4e3a\u5bfc\u81f4\u7684\uff1a let: \u5b9a\u4e49let\u53d8\u91cf\u540e\uff0c\u5728\u4f7f\u7528\u524d\u5fc5\u987b\u5bf9\u5176\u521d\u59cb\u5316\uff0c\u5426\u5219\u4f1a\u5bfc\u81f4\u5f15\u7528\u9519\u8bef\u3002 const: \u5b9a\u4e49const\u53d8\u91cf\u540e\uff0c\u5fc5\u987b\u5bf9\u5176\u521d\u59cb\u5316\uff0c\u5e76\u4e14\u4e0d\u80fd\u5728\u4e4b\u540e\u91cd\u65b0\u8d4b\u503c\u3002 \u5728\u4e0a\u8ff0\u793a\u4f8b\u4e2d\uff0c\u7531\u4e8elet PI\u662f\u5728const PI\u4e4b\u540e\u5b9a\u4e49\u7684\uff0c\u56e0\u6b64\u5728\u4f7f\u7528\u524d\u5fc5\u987b\u5bf9\u5176\u521d\u59cb\u5316\u3002\u7531\u4e8elet\u53d8\u91cf\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c\uff0c\u56e0\u6b64\u4e0a\u65b9\u7684\u4ee3\u7801\u4e0d\u4f1a\u62a5\u9519\uff0c\u5e76\u6210\u529f\u5c06PI\u8d4b\u503c\u4e3a&#8221;2222&#8243;\u3002 \u9700\u8981\u6ce8\u610f\u7684\u662f\uff0cconst\u5e76\u4e0d\u662f\u771f\u6b63\u610f\u4e49\u4e0a\u7684\u5e38\u91cf\uff0c\u5b83\u5b9e\u9645\u4e0a\u662f\u4e00\u79cd\u5f15\u7528\u7c7b\u578b\u3002\u5bf9\u4e8e\u5f15\u7528\u7c7b\u578b\uff0c\u6211\u4eec\u65e0\u6cd5\u6539\u53d8\u5176\u5f15\u7528\u5730\u5740\uff0c\u4f46\u53ef\u4ee5\u6539\u53d8\u5176\u5185\u90e8\u6570\u636e\u3002\u56e0\u6b64\uff0c\u5728\u4f7f\u7528const\u5b9a\u4e49\u5bf9\u8c61\u6216\u6570\u7ec4\u65f6\uff0c\u53ef\u4ee5\u4fee\u6539\u5176\u5185\u90e8\u6570\u636e\uff0c\u4f46\u65e0\u6cd5\u91cd\u65b0\u8d4b\u503c\u6574\u4e2a\u5bf9\u8c61\u6216\u6570\u7ec4\u3002 \u4ee5\u4e0a\u5c31\u662fES6 \u4e2d const \u548c let \u7684\uff1a\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c const \u5b9a\u4e49\u7684\u53d8\u91cf\uff1f\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-3742","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/3742","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=3742"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/3742\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=3742"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=3742"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=3742"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}