{"id":32303,"date":"2024-11-25T15:22:56","date_gmt":"2024-11-25T07:22:56","guid":{"rendered":"https:\/\/fwq.ai\/blog\/32303\/"},"modified":"2024-11-25T15:22:56","modified_gmt":"2024-11-25T07:22:56","slug":"%e4%bd%bf%e7%94%a8javascript%e8%bf%ad%e4%bb%a3%e5%af%b9%e8%b1%a1%e9%94%ae%e7%9a%84%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/32303\/","title":{"rendered":"\u4f7f\u7528JavaScript\u8fed\u4ee3\u5bf9\u8c61\u952e\u7684\u65b9\u6cd5"},"content":{"rendered":"

\"\u4f7f\u7528JavaScript\u8fed\u4ee3\u5bf9\u8c61\u952e\u7684\u65b9\u6cd5\u63d2\u56fe\"<\/p>\n

\u81ea\u5b9a\u4e49\u5bf9\u8c61\u65e0\u6cd5\u4f7f\u7528 for…of \u5faa\u73af\u8fdb\u884c\u8fed\u4ee3\u3002\u6b64\u5916\uff0c\u60a8\u4e0d\u80fd\u4f7f\u7528 map() \u548c forEach() \u7b49\u8fed\u4ee3\u5668\u65b9\u6cd5\u3002\u5982\u679c\u8fd9\u6837\u505a\uff0c\u60a8\u5c06\u5728\u6bcf\u4e2a\u5b9e\u4f8b\u4e2d\u6536\u5230 TypeError \u3002 <\/span><\/p>\n

\u76f8\u53cd\uff0c\u8bf7\u4f7f\u7528<\/span> for…in \u6765\u8fed\u4ee3\u5bf9\u8c61\u3002\u6b64\u65b9\u6cd5\u8fed\u4ee3\u5bf9\u8c61\u7684\u6240\u6709\u53ef\u679a\u4e3e\u3001\u975e\u7b26\u53f7\u5c5e\u6027\u3002<\/span><\/p>\n

\u5728\u4e0b\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u4f7f\u7528\u5b83\u6765\u8fed\u4ee3 obj \u7684\u6240\u6709\u4e09\u4e2a\u5c5e\u6027\uff0c\u5e76\u4e14\u5bf9\u4e8e\u6bcf\u4e2a\u5c5e\u6027\uff0c\u6211\u4eec\u8bb0\u5f55\u4e00\u4e2a\u7531\u5c5e\u6027\u540d\u79f0\uff08\u5373\u5176\u952e\uff09\u53ca\u5176\u76f8\u5e94\u503c\u7ec4\u6210\u7684\u5b57\u7b26\u4e32\u3002<\/span><\/p>\n

var obj = {a: 1, b: 2, c: 3};\n\nfor (const prop in obj) {\n  console.log(`obj.${prop} = ${obj[prop]}`);\n}\n\n\/\/ Output:\n\/\/ \"obj.a = 1\"\n\/\/ \"obj.b = 2\"\n\/\/ \"obj.c = 3\"\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6211\u4eec\u4f7f\u7528\u53d8\u91cf prop \u521d\u59cb\u5316\u5faa\u73af\uff0c\u8be5\u53d8\u91cf\u5c06\u5728\u5bf9\u8c61\u5c5e\u6027\u7684\u6bcf\u6b21\u8fed\u4ee3\u4e2d\u4fdd\u5b58\u4e0d\u540c\u7684\u5c5e\u6027\u540d\u79f0\uff08\u4e5f\u79f0\u4e3a\u952e\uff09\u3002\u5757\u4e2d\u6307\u5b9a\u7684\u4ee3\u7801\u5c06\u5728\u6bcf\u6b21\u8fed\u4ee3\u65f6\u8fd0\u884c\u3002<\/p>\n
\u7acb\u5373\u5b66\u4e60<\/span>\u201c\u201d\uff1b<\/p>\n
\u8fd9\u91cc\u6709\u4e00\u4e2a\u5c0f\u6f14\u793a\u6765\u6f14\u793a\u8fd9\u4e00\u70b9\uff08\u5355\u51fb\u7ed3\u679c<\/strong>\u67e5\u770b\u8f93\u51fa\uff09\uff1a<\/p>\n<\/p>\n
\u5728\u5faa\u73af\u5185\uff0c\u6bcf\u6b21\u8fed\u4ee3\u65f6\uff0c\u6211\u4eec\u90fd\u4f1a\u5c06\u5bf9\u8c61\u7684\u5c5e\u6027\u540d\u79f0\u548c\u503c\u4e4b\u4e00\u8bb0\u5f55\u5230\u63a7\u5236\u53f0\u3002<\/span><\/p>\n
\u8fed\u4ee3\u5bf9\u8c61\u5c5e\u6027\u7684\u53e6\u4e00\u79cd\u65b9\u6cd5\u662f\u5c06\u5bf9\u8c61\u4f20\u9012\u5230 Object.entries() \u4e2d\u5e76\u8c03\u7528\u8be5\u65b9\u6cd5\u3002\u8fd9\u5c06\u8fd4\u56de\u591a\u7ef4\u6570\u7ec4\uff08\u6570\u7ec4\u7684\u6570\u7ec4\uff09\u5185\u8be5\u5bf9\u8c61\u7684\u6240\u6709\u53ef\u679a\u4e3e\u5c5e\u6027\uff1a<\/span><\/p>\n
const obj = {a: 1, b: 2, c: 3};\n\nlet result = Object.entries(obj)\n\nconsole.log(result)\n\/\/ [[\"a\", 1], [\"b\", 2], [\"c\", 3]]\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u7136\u540e\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4efb\u4f55\u6570\u7ec4\u8fed\u4ee3\u5668\u65b9\u6cd5\u5faa\u73af\u5b83\uff1a<\/span><\/p>\n
Object.entries(obj).forEach(entry =&gt; {\n  \/\/ do something\n})\n\nObject.entries(obj).map(entry =&gt; {\n  \/\/ do something\n})\n\nObject.entries(obj).every(entry =&gt; {\n  \/\/ do something\n})\n\n\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528 for…of \u5faa\u73af\uff1a<\/p>\n
for (const entry of Object.entries(obj)) {\n  \/\/ do something\n}\n\nfor (const [key, value] of Object.entries(obj)) {\n  \/\/ do something\n}\n<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u4ee5\u4e0b\u662f\u4e00\u4e9b\u6f14\u793a\uff1a<\/p>\n<\/p>\n
\u5728\u8fd9\u91cc\uff0c\u56e0\u4e3a\u6211\u4eec\u5728\u6bcf\u6b21\u8fed\u4ee3\u4e2d\u5f97\u5230\u4e00\u4e2a\u7531\u952e\u548c\u503c\u7ec4\u6210\u7684\u6570\u7ec4\uff0c\u6240\u4ee5\u6211\u4eec\u53ea\u9700\u5206\u522b\u4f7f\u7528 entry[0] \u548c entry[1] \u6765\u8bbf\u95ee\u5b83\u4eec\u3002\u5982\u679c\u60a8\u53ea\u9700\u8981\u952e\u800c\u4e0d\u662f\u952e\u548c\u503c\uff0c\u8bf7\u4f7f\u7528 Object.keys() \u4ee3\u66ff Object.entries()\u3002<\/p>\n
for…of \u57fa\u672c\u76f8\u540c\uff1a<\/p>\n<\/p>\n
\u7ed3\u8bba<\/h2>\n
\u8fd9\u4e9b\u662f\u6211\u4eec\u53ef\u4ee5\u5728 JavaScript \u4e2d\u8f7b\u677e\u8fed\u4ee3\u5bf9\u8c61\u7684\u5c5e\u6027\u548c\u952e\u7684\u65b9\u6cd5\u3002\u67e5\u770b\u6211\u4eec\u7684 JavaScript \u5e16\u5b50\u4ee5\u83b7\u53d6\u66f4\u591a\u6587\u7ae0\u548c\u6559\u7a0b\u3002<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u4f7f\u7528JavaScript\u8fed\u4ee3\u5bf9\u8c61\u952e\u7684\u65b9\u6cd5\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":"
\u81ea\u5b9a\u4e49\u5bf9\u8c61\u65e0\u6cd5\u4f7f\u7528 for…of \u5faa\u73af\u8fdb\u884c\u8fed\u4ee3\u3002\u6b64\u5916\uff0c\u60a8\u4e0d\u80fd\u4f7f\u7528 map() \u548c forEach() \u7b49\u8fed\u4ee3\u5668\u65b9\u6cd5\u3002\u5982\u679c\u8fd9\u6837\u505a\uff0c\u60a8\u5c06\u5728\u6bcf\u4e2a\u5b9e\u4f8b\u4e2d\u6536\u5230 TypeError \u3002 \u76f8\u53cd\uff0c\u8bf7\u4f7f\u7528 for…in \u6765\u8fed\u4ee3\u5bf9\u8c61\u3002\u6b64\u65b9\u6cd5\u8fed\u4ee3\u5bf9\u8c61\u7684\u6240\u6709\u53ef\u679a\u4e3e\u3001\u975e\u7b26\u53f7\u5c5e\u6027\u3002 \u5728\u4e0b\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u4f7f\u7528\u5b83\u6765\u8fed\u4ee3 obj \u7684\u6240\u6709\u4e09\u4e2a\u5c5e\u6027\uff0c\u5e76\u4e14\u5bf9\u4e8e\u6bcf\u4e2a\u5c5e\u6027\uff0c\u6211\u4eec\u8bb0\u5f55\u4e00\u4e2a\u7531\u5c5e\u6027\u540d\u79f0\uff08\u5373\u5176\u952e\uff09\u53ca\u5176\u76f8\u5e94\u503c\u7ec4\u6210\u7684\u5b57\u7b26\u4e32\u3002 var obj = {a: 1, b: 2, c: 3}; for (const prop in obj) { console.log(`obj.${prop} = ${obj[prop]}`); } \/\/ Output: \/\/ “obj.a = 1” \/\/ “obj.b = 2” \/\/ “obj.c = 3” \u767b\u5f55\u540e\u590d\u5236 \u6211\u4eec\u4f7f\u7528\u53d8\u91cf prop \u521d\u59cb\u5316\u5faa\u73af\uff0c\u8be5\u53d8\u91cf\u5c06\u5728\u5bf9\u8c61\u5c5e\u6027\u7684\u6bcf\u6b21\u8fed\u4ee3\u4e2d\u4fdd\u5b58\u4e0d\u540c\u7684\u5c5e\u6027\u540d\u79f0\uff08\u4e5f\u79f0\u4e3a\u952e\uff09\u3002\u5757\u4e2d\u6307\u5b9a\u7684\u4ee3\u7801\u5c06\u5728\u6bcf\u6b21\u8fed\u4ee3\u65f6\u8fd0\u884c\u3002 \u7acb\u5373\u5b66\u4e60\u201c\u201d\uff1b \u8fd9\u91cc\u6709\u4e00\u4e2a\u5c0f\u6f14\u793a\u6765\u6f14\u793a\u8fd9\u4e00\u70b9\uff08\u5355\u51fb\u7ed3\u679c\u67e5\u770b\u8f93\u51fa\uff09\uff1a \u5728\u5faa\u73af\u5185\uff0c\u6bcf\u6b21\u8fed\u4ee3\u65f6\uff0c\u6211\u4eec\u90fd\u4f1a\u5c06\u5bf9\u8c61\u7684\u5c5e\u6027\u540d\u79f0\u548c\u503c\u4e4b\u4e00\u8bb0\u5f55\u5230\u63a7\u5236\u53f0\u3002 \u8fed\u4ee3\u5bf9\u8c61\u5c5e\u6027\u7684\u53e6\u4e00\u79cd\u65b9\u6cd5\u662f\u5c06\u5bf9\u8c61\u4f20\u9012\u5230 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18],"tags":[],"class_list":["post-32303","post","type-post","status-publish","format-standard","hentry","category-cms"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/32303","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=32303"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/32303\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=32303"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=32303"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=32303"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}