{"id":3761,"date":"2024-11-10T17:30:36","date_gmt":"2024-11-10T09:30:36","guid":{"rendered":"https:\/\/fwq.ai\/blog\/3761\/"},"modified":"2024-11-10T17:30:36","modified_gmt":"2024-11-10T09:30:36","slug":"es6%e4%b8%adconst%e5%a3%b0%e6%98%8e%e7%9a%84%e5%b8%b8%e9%87%8f%e5%8f%af%e4%bb%a5%e4%bf%ae%e6%94%b9%e5%90%97%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/3761\/","title":{"rendered":"ES6\u4e2dconst\u58f0\u660e\u7684\u5e38\u91cf\u53ef\u4ee5\u4fee\u6539\u5417\uff1f"},"content":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/001\/246\/273\/173113335384168.jpg\" class=\"aligncenter\" title=\"ES6\u4e2dconst\u58f0\u660e\u7684\u5e38\u91cf\u53ef\u4ee5\u4fee\u6539\u5417\uff1f\u63d2\u56fe\" alt=\"ES6\u4e2dconst\u58f0\u660e\u7684\u5e38\u91cf\u53ef\u4ee5\u4fee\u6539\u5417\uff1f\u63d2\u56fe\" \/><\/p>\n<p><strong>es6\u5e38\u91cf\u4fee\u6539\u7591\u95ee<\/strong><\/p>\n<p>es6\u4e2d\u5f15\u5165\u7684const\u5173\u952e\u5b57\u7528\u4e8e\u5b9a\u4e49\u5e38\u91cf\uff0c\u4e00\u65e6\u58f0\u660e\u4e14\u521d\u59cb\u5316\u540e\uff0c\u4e0d\u53ef\u518d\u4fee\u6539\u5176\u503c\u3002\u7136\u800c\uff0c\u5728\u4ee5\u4e0b\u4ee3\u7801\u4e2d\uff0c\u5373\u4f7f\u5c06const\u5173\u952e\u5b57\u540e\u52a0\u4e0alet\uff0c\u5374\u4ecd\u7136\u53ef\u4ee5\u4fee\u6539pi\u7684\u503c\uff1a<\/p>\n<pre>const PI = '3.14';\nconsole.log(PI);\nPI = '3.15555'; \/\/ \u62a5\u9519\uff0c\u5e38\u91cf\u4e0d\u53ef\u4fee\u6539\nlet PI = '2222';  \/\/ \u4e0d\u62a5\u9519\uff0c\u53ef\u4ee5\u4fee\u6539<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p><strong>\u91ca\u7591<\/strong><\/p>\n<p>let\u548cconst\u90fd\u662f\u58f0\u660e\u53d8\u91cf\u524d\u5fc5\u987b\u4f7f\u7528\uff0c\u5b9a\u4e49\u540e\u624d\u80fd\u8bbf\u95ee\u7684\u9650\u5b9a\u7b26\u3002\u4f46\u5176\u4e3b\u8981\u5728\u4e8e\uff1a<\/p>\n<ul>\n<li> <strong>let\uff1a<\/strong>\u58f0\u660e\u53ef\u4fee\u6539\u7684\u53d8\u91cf\u3002<\/li>\n<li> <strong>const\uff1a<\/strong>\u58f0\u660e\u5e38\u91cf\uff0c\u4e0d\u53ef\u4fee\u6539\u3002<\/li>\n<\/ul>\n<p>\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c\u5f53\u4f7f\u7528const\u58f0\u660epi\u540e\uff0c\u7531\u4e8e\u5176\u4e3a\u5e38\u91cf\uff0c\u56e0\u6b64pi\u7684\u503c\u4e0d\u53ef\u4fee\u6539\uff0c\u4ee3\u7801\u4e2d\u7684\u8d4b\u503c\u8bed\u53e5\u4f1a\u62a5\u9519\u3002<\/p>\n<p>\u7136\u800c\uff0c\u540e\u9762\u7684let pi = &#8216;2222&#8217;\u4e4b\u6240\u4ee5\u4e0d\u62a5\u9519\uff0c\u662f\u56e0\u4e3a\uff1a<\/p>\n<ul>\n<li>const\u58f0\u660e\u7684pi\u53d8\u91cf\u5b9e\u9645\u4e0a\u662f\u5e38\u91cf\u5f15\u7528\uff0c\u6307\u5411\u5185\u5b58\u4e2d\u7684\u4e00\u6bb5\u5185\u5b58\u7a7a\u95f4\uff0c\u8be5\u5185\u5b58\u7a7a\u95f4\u5b58\u50a8\u4e86\u503c&#8217;3.14&#8217;\u3002<\/li>\n<li>let\u58f0\u660e\u7684pi\u53d8\u91cf\u4e5f\u662f\u4e00\u4e2a\u5f15\u7528\uff0c\u6307\u5411\u53e6\u4e00\u4e2a\u5185\u5b58\u7a7a\u95f4\uff0c\u8be5\u5185\u5b58\u7a7a\u95f4\u5b58\u50a8\u4e86\u503c&#8217;2222&#8217;\u3002<\/li>\n<\/ul>\n<p>\u56e0\u6b64\uff0c\u5c3d\u7ba1\u90fd\u4f7f\u7528\u4e86\u76f8\u540c\u7684\u540d\u79f0pi\uff0c\u4f46\u5b83\u4eec\u6307\u5411\u4e0d\u540c\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u4fee\u6539let\u58f0\u660e\u7684pi\u503c\u4e0d\u4f1a\u5f71\u54cdconst\u58f0\u660e\u7684pi\u503c\u3002<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fES6\u4e2dconst\u58f0\u660e\u7684\u5e38\u91cf\u53ef\u4ee5\u4fee\u6539\u5417\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\u5e38\u91cf\u4fee\u6539\u7591\u95ee es6\u4e2d\u5f15\u5165\u7684const\u5173\u952e\u5b57\u7528\u4e8e\u5b9a\u4e49\u5e38\u91cf\uff0c\u4e00\u65e6\u58f0\u660e\u4e14\u521d\u59cb\u5316\u540e\uff0c\u4e0d\u53ef\u518d\u4fee\u6539\u5176\u503c\u3002\u7136\u800c\uff0c\u5728\u4ee5\u4e0b\u4ee3\u7801\u4e2d\uff0c\u5373\u4f7f\u5c06const\u5173\u952e\u5b57\u540e\u52a0\u4e0alet\uff0c\u5374\u4ecd\u7136\u53ef\u4ee5\u4fee\u6539pi\u7684\u503c\uff1a const PI = &#8216;3.14&#8217;; console.log(PI); PI = &#8216;3.15555&#8217;; \/\/ \u62a5\u9519\uff0c\u5e38\u91cf\u4e0d\u53ef\u4fee\u6539 let PI = &#8216;2222&#8217;; \/\/ \u4e0d\u62a5\u9519\uff0c\u53ef\u4ee5\u4fee\u6539 \u767b\u5f55\u540e\u590d\u5236 \u91ca\u7591 let\u548cconst\u90fd\u662f\u58f0\u660e\u53d8\u91cf\u524d\u5fc5\u987b\u4f7f\u7528\uff0c\u5b9a\u4e49\u540e\u624d\u80fd\u8bbf\u95ee\u7684\u9650\u5b9a\u7b26\u3002\u4f46\u5176\u4e3b\u8981\u5728\u4e8e\uff1a let\uff1a\u58f0\u660e\u53ef\u4fee\u6539\u7684\u53d8\u91cf\u3002 const\uff1a\u58f0\u660e\u5e38\u91cf\uff0c\u4e0d\u53ef\u4fee\u6539\u3002 \u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c\u5f53\u4f7f\u7528const\u58f0\u660epi\u540e\uff0c\u7531\u4e8e\u5176\u4e3a\u5e38\u91cf\uff0c\u56e0\u6b64pi\u7684\u503c\u4e0d\u53ef\u4fee\u6539\uff0c\u4ee3\u7801\u4e2d\u7684\u8d4b\u503c\u8bed\u53e5\u4f1a\u62a5\u9519\u3002 \u7136\u800c\uff0c\u540e\u9762\u7684let pi = &#8216;2222&#8217;\u4e4b\u6240\u4ee5\u4e0d\u62a5\u9519\uff0c\u662f\u56e0\u4e3a\uff1a const\u58f0\u660e\u7684pi\u53d8\u91cf\u5b9e\u9645\u4e0a\u662f\u5e38\u91cf\u5f15\u7528\uff0c\u6307\u5411\u5185\u5b58\u4e2d\u7684\u4e00\u6bb5\u5185\u5b58\u7a7a\u95f4\uff0c\u8be5\u5185\u5b58\u7a7a\u95f4\u5b58\u50a8\u4e86\u503c&#8217;3.14&#8217;\u3002 let\u58f0\u660e\u7684pi\u53d8\u91cf\u4e5f\u662f\u4e00\u4e2a\u5f15\u7528\uff0c\u6307\u5411\u53e6\u4e00\u4e2a\u5185\u5b58\u7a7a\u95f4\uff0c\u8be5\u5185\u5b58\u7a7a\u95f4\u5b58\u50a8\u4e86\u503c&#8217;2222&#8217;\u3002 \u56e0\u6b64\uff0c\u5c3d\u7ba1\u90fd\u4f7f\u7528\u4e86\u76f8\u540c\u7684\u540d\u79f0pi\uff0c\u4f46\u5b83\u4eec\u6307\u5411\u4e0d\u540c\u7684\u5185\u5b58\u7a7a\u95f4\uff0c\u4fee\u6539let\u58f0\u660e\u7684pi\u503c\u4e0d\u4f1a\u5f71\u54cdconst\u58f0\u660e\u7684pi\u503c\u3002 \u4ee5\u4e0a\u5c31\u662fES6\u4e2dconst\u58f0\u660e\u7684\u5e38\u91cf\u53ef\u4ee5\u4fee\u6539\u5417\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-3761","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/3761","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=3761"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/3761\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=3761"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=3761"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=3761"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}