{"id":4066,"date":"2024-11-10T13:39:23","date_gmt":"2024-11-10T05:39:23","guid":{"rendered":"https:\/\/fwq.ai\/blog\/4066\/"},"modified":"2024-11-10T13:39:23","modified_gmt":"2024-11-10T05:39:23","slug":"javascript-%e4%b8%ad-var-%e5%92%8c-let-%e5%85%b3%e9%94%ae%e5%ad%97%e5%a3%b0%e6%98%8e%e5%8f%98%e9%87%8f%e7%9a%84%e5%8c%ba%e5%88%ab%e6%98%af%e4%bb%80%e4%b9%88%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/4066\/","title":{"rendered":"JavaScript \u4e2d var \u548c let \u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u533a\u522b\u662f\u4ec0\u4e48\uff1f"},"content":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/001\/246\/273\/173121931380973.jpg\" class=\"aligncenter\" title=\"JavaScript \u4e2d var \u548c let \u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u533a\u522b\u662f\u4ec0\u4e48\uff1f\u63d2\u56fe\" alt=\"JavaScript \u4e2d var \u548c let \u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u533a\u522b\u662f\u4ec0\u4e48\uff1f\u63d2\u56fe\" \/><\/p>\n<p><strong>js\u4e2dvar\u548clet\u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u5dee\u5f02<\/strong><\/p>\n<p>\u5728JavaScript\u4e2d\uff0c\u58f0\u660e\u53d8\u91cf\u53ef\u4ee5\u4f7f\u7528var\u548clet\u5173\u952e\u5b57\u3002\u4e0b\u9762\u4ecb\u7ecd\u5176\uff1a<\/p>\n<p><strong>\u8303\u56f4<\/strong><\/p>\n<ul>\n<li>var\u58f0\u660e\u7684\u53d8\u91cf\u5177\u6709\u5168\u5c40\uff0c\u53ef\u4ee5\u5728\u6574\u4e2a\u811a\u672c\u4e2d\u8bbf\u95ee\u3002<\/li>\n<li>let\u58f0\u660e\u7684\u53d8\u91cf\u5177\u6709\u5757\u7ea7\u4f5c\u7528\u57df\uff0c\u4ec5\u5728\u58f0\u660e\u5757\u5185\u53ef\u8bbf\u95ee\u3002<\/li>\n<\/ul>\n<p><strong>\u91cd\u65b0\u58f0\u660e<\/strong><\/p>\n<p><span>\u7acb\u5373\u5b66\u4e60<\/span>\u201c\u201d\uff1b<\/p>\n<ul>\n<li>var\u58f0\u660e\u7684\u53d8\u91cf\u53ef\u4ee5\u5728\u540c\u4e00\u4e0b\u4e00\u4e2a\u4f5c\u7528\u57df\u4e2d\u91cd\u65b0\u58f0\u660e\u3002<\/li>\n<li>let\u58f0\u660e\u7684\u53d8\u91cf\u5982\u679c\u5728\u540c\u4e00\u4e2a\u5757\u7ea7\u4f5c\u7528\u57df\u5185\u88ab\u91cd\u65b0\u58f0\u660e\uff0c\u4f1a\u62a5\u9519\u3002<\/li>\n<\/ul>\n<p><strong>\u518d\u8d4b\u503c<\/strong><\/p>\n<ul>\n<li>var\u548clet\u58f0\u660e\u7684\u53d8\u91cf\u90fd\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c\u3002<\/li>\n<\/ul>\n<p><strong>const<\/strong><\/p>\n<p>\u9664\u4e86var\u548clet\uff0c\u8fd8\u6709const\u5173\u952e\u5b57\u53ef\u4ee5\u58f0\u660e\u5c40\u90e8\u53d8\u91cf\u3002\u4e0elet\u7c7b\u4f3c\uff0cconst\u58f0\u660e\u7684\u53d8\u91cf\u5177\u6709\u5757\u7ea7\u4f5c\u7528\u57df\uff0c\u4f46\u662f\u65e0\u6cd5\u91cd\u65b0\u8d4b\u503c\u3002<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fJavaScript \u4e2d var \u548c let \u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u662f\u4ec0\u4e48\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>js\u4e2dvar\u548clet\u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u5dee\u5f02 \u5728JavaScript\u4e2d\uff0c\u58f0\u660e\u53d8\u91cf\u53ef\u4ee5\u4f7f\u7528var\u548clet\u5173\u952e\u5b57\u3002\u4e0b\u9762\u4ecb\u7ecd\u5176\uff1a \u8303\u56f4 var\u58f0\u660e\u7684\u53d8\u91cf\u5177\u6709\u5168\u5c40\uff0c\u53ef\u4ee5\u5728\u6574\u4e2a\u811a\u672c\u4e2d\u8bbf\u95ee\u3002 let\u58f0\u660e\u7684\u53d8\u91cf\u5177\u6709\u5757\u7ea7\u4f5c\u7528\u57df\uff0c\u4ec5\u5728\u58f0\u660e\u5757\u5185\u53ef\u8bbf\u95ee\u3002 \u91cd\u65b0\u58f0\u660e \u7acb\u5373\u5b66\u4e60\u201c\u201d\uff1b var\u58f0\u660e\u7684\u53d8\u91cf\u53ef\u4ee5\u5728\u540c\u4e00\u4e0b\u4e00\u4e2a\u4f5c\u7528\u57df\u4e2d\u91cd\u65b0\u58f0\u660e\u3002 let\u58f0\u660e\u7684\u53d8\u91cf\u5982\u679c\u5728\u540c\u4e00\u4e2a\u5757\u7ea7\u4f5c\u7528\u57df\u5185\u88ab\u91cd\u65b0\u58f0\u660e\uff0c\u4f1a\u62a5\u9519\u3002 \u518d\u8d4b\u503c var\u548clet\u58f0\u660e\u7684\u53d8\u91cf\u90fd\u53ef\u4ee5\u91cd\u65b0\u8d4b\u503c\u3002 const \u9664\u4e86var\u548clet\uff0c\u8fd8\u6709const\u5173\u952e\u5b57\u53ef\u4ee5\u58f0\u660e\u5c40\u90e8\u53d8\u91cf\u3002\u4e0elet\u7c7b\u4f3c\uff0cconst\u58f0\u660e\u7684\u53d8\u91cf\u5177\u6709\u5757\u7ea7\u4f5c\u7528\u57df\uff0c\u4f46\u662f\u65e0\u6cd5\u91cd\u65b0\u8d4b\u503c\u3002 \u4ee5\u4e0a\u5c31\u662fJavaScript \u4e2d var \u548c let \u5173\u952e\u5b57\u58f0\u660e\u53d8\u91cf\u7684\u662f\u4ec0\u4e48\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-4066","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/4066","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=4066"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/4066\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=4066"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=4066"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=4066"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}