{"id":52582,"date":"2024-12-03T08:17:35","date_gmt":"2024-12-03T00:17:35","guid":{"rendered":"https:\/\/fwq.ai\/blog\/52582\/"},"modified":"2024-12-03T08:17:35","modified_gmt":"2024-12-03T00:17:35","slug":"%e7%b1%bb%e5%9e%8b%e5%ae%9e%e7%94%a8%e7%a8%8b%e5%ba%8f-javascript-%e6%8c%91%e6%88%98","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/52582\/","title":{"rendered":"\u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f – JavaScript \u6311\u6218"},"content":{"rendered":"

<\/b> <\/p>\n

\u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f – JavaScript \u6311\u6218<\/h1>\n

<\/i>\u6536\u85cf<\/span> <\/p>\n

\u672c\u7bc7\u6587\u7ae0\u4e3b\u8981\u662f\u7ed3\u5408\u6211\u4e4b\u524d\u9762\u8bd5\u7684\u5404\u79cd\u7ecf\u5386\u548c\u5b9e\u6218\u5f00\u53d1\u4e2d\u9047\u5230\u7684\u95ee\u9898\u89e3\u51b3\u7ecf\u9a8c\u6574\u7406\u7684\uff0c\u5e0c\u671b\u8fd9\u7bc7\u300a\u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f – JavaScript \u6311\u6218\u300b\u5bf9\u4f60\u6709\u5f88\u5927\u5e2e\u52a9\uff01\u6b22\u8fce\u6536\u85cf\uff0c\u5206\u4eab\u7ed9\u66f4\u591a\u7684\u9700\u8981\u7684\u670b\u53cb\u5b66\u4e60~<\/p>\n

\"\u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f<\/p>\n

\u4ecb\u7ecd <\/h2>\n

\u68c0\u67e5\u7c7b\u578b\u662f\u65e5\u5e38\u7f16\u7801\u548c\u6280\u672f\u9762\u8bd5\u4e2d javascript \u7684\u5e38\u89c1\u505a\u6cd5\u3002<\/p>\n

\u60a8\u53ef\u4ee5\u5728 github \u4e0a\u627e\u5230\u8fd9\u7bc7\u6587\u7ae0\u4e2d\u7684\u6240\u6709\u4ee3\u7801\u3002<\/p>\n

\n

\u539f\u59cb\u503c <\/h3>\n

\u5728 javascript \u4e2d\uff0c\u9664 object \u4e4b\u5916\u7684\u6240\u6709\u7c7b\u578b\u90fd\u5b9a\u4e49\u76f4\u63a5\u5728\u8bed\u8a00\u6700\u4f4e\u7ea7\u522b\u8868\u793a\u7684\u4e0d\u53ef\u53d8\u503c\u3002\u6211\u4eec\u5c06\u8fd9\u4e9b\u7c7b\u578b\u7684\u503c\u79f0\u4e3a\u539f\u59cb\u503c<\/em>\u3002 <\/p>\n

\u6709 7 \u4e2a\u539f\u59cb\u503c\uff1a<\/p>\n

    \n
  1. \u7a7a<\/li>\n
  2. \u672a\u5b9a\u4e49<\/li>\n
  3. \u5e03\u5c14\u503c<\/li>\n
  4. \u6570\u5b57<\/li>\n
  5. bigint<\/li>\n
  6. \u5b57\u7b26\u4e32<\/li>\n
  7. \u7b26\u53f7<\/li>\n<\/ol>\n

    \u9664 null \u4e4b\u5916\u7684\u6240\u6709\u539f\u59cb\u7c7b\u578b\u90fd\u53ef\u4ee5\u901a\u8fc7 typeof \u8fd0\u7b97\u7b26\u8fdb\u884c\u6d4b\u8bd5\u3002 typeof null \u8fd4\u56de\u201cobject\u201d\uff0c\u56e0\u6b64\u5fc5\u987b\u4f7f\u7528 === null \u6765\u6d4b\u8bd5 null\u3002<\/p>\n

    \u56e0\u6b64\uff0c\u6211\u4eec\u5f97\u5230\u4e86\u7b2c\u4e00\u79cd\u7c7b\u578b\u7684\u6548\u7528\u51fd\u6570\u3002<\/p>\n

    function isboolean(value) {\n  return typeof value === 'boolean';\n}\n\nfunction isstring(value) {\n  return typeof value === 'string';\n}\n\nfunction isnumber(value) {\n  return typeof value === 'number';\n}\n\nfunction issymbol(value) {\n  return typeof value === 'symbol';\n}\n\nfunction isbigint(value) {\n  return typeof value === 'bigint';\n}\n\nfunction isundefined(value) {\n  return typeof value === 'undefined';\n}\n\nfunction isnull(value) {\n  return value === null;\n}\n\n\/\/ usage example\nconsole.log(issymbol(symbol('test'))); \/\/ => true\nconsole.log(isnull(null)); \/\/ => true\nconsole.log(isundefined(undefined)); \/\/ => true\nconsole.log(isnumber(1)); \/\/ => true\nconsole.log(isstring('')); \/\/ => true\nconsole.log(isboolean(true)); \/\/ => true\nconsole.log(isbigint(9007199254740991n)); \/\/ => true\n<\/pre>\n
    \n
     \u5bf9\u8c61 <\/h3>\n
    \u6240\u6709\u4e0d\u662f\u539f\u59cb\u7c7b\u578b\u7684\u4e1c\u897f\u90fd\u662f javascript \u4e2d\u7684\u5bf9\u8c61\u3002\u8fd9\u5305\u62ec\uff1a<\/p>\n
      \n
    • \u666e\u901a\u7269\u4f53<\/li>\n
    • \u6570\u7ec4<\/li>\n
    • \u529f\u80fd<\/li>\n
    • \u65e5\u671f<\/li>\n
    • \u6b63\u5219\u8868\u8fbe\u5f0f<\/li>\n
    • \u5176\u4ed6\u5185\u7f6e\u5bf9\u8c61\u7c7b\u578b<\/li>\n<\/ul>\n
      \u8fd9\u662f\u6570\u7ec4\u3001\u51fd\u6570\u3001\u5bf9\u8c61\u7684\u7b2c\u4e8c\u4e2a\u5b9e\u7528\u51fd\u6570\u3002<\/p>\n
      function isarray(value) {\n  return array.isarray(value);\n}\n\nfunction isfunction(value) {\n  return typeof value === 'function';\n}\n\nfunction isobject(value) {\n  \/\/ for null and undefined\n  if (value == null) {\n    return false;\n  }\n\n  return typeof value === 'object';\n}\n\nfunction isplainobject(value) {\n  \/\/ for null and undefined\n  if (value == null) {\n    return false;\n  }\n\n  const prototype = object.getprototypeof(value);\n  return prototype === object.prototype || prototype === null;\n}\n\n\/\/ usage example\nconsole.log(isarray(new array())); \/\/ => true\nconsole.log(isobject(object(null))); \/\/ => true\nconsole.log(isfunction(object.prototype.tostring)); \/\/ => true\nconsole.log(isplainobject(object.create(null))); \/\/ => true\n<\/pre>\n
      \n
       object.prototype.tostring.call() <\/h3>\n
      javascript \u4e2d\u6709\u591a\u79cd\u68c0\u67e5\u7c7b\u578b\u7684\u65b9\u6cd5\uff0c\u5305\u62ec\uff1a<\/p>\n
        \n
      •  typeof \u9002\u7528\u4e8e\u9664 null \u4e4b\u5916\u7684\u6240\u6709\u539f\u59cb\u7c7b\u578b\u3002<\/li>\n
      •  instanceof \u786e\u5b9a\u5bf9\u8c61\u662f\u5426\u662f\u7279\u5b9a\u6784\u9020\u51fd\u6570\u6216\u7c7b\u7684\u5b9e\u4f8b\u3002\u5b83\u4e0d\u9002\u7528\u4e8e\u539f\u59cb\u503c\u3002<\/li>\n<\/ul>\n
        object.prototype.tostring.call() \u662f javascript \u4e2d\u6700\u53ef\u9760\u7684\u7c7b\u578b\u68c0\u67e5\u65b9\u6cd5\u3002<\/p>\n
        \u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u63d0\u53d6\u7c7b\u578b\uff1a<\/p>\n
        function getType(value) {\n  const type = typeof value;\n\n  if (type !== 'object') {\n    return type;\n  }\n\n  return Object.prototype.toString\n    .call(value)\n    .slice(8, -1)\n    .toLowerCase();\n}\n\n\/\/ Usage example\nconsole.log(getType(1)); \/\/ => number\nconsole.log(getType('')); \/\/ => string\nconsole.log(getType({})); \/\/ => object\nconsole.log(getType(null)); \/\/ => null\nconsole.log(getType(undefined)); \/\/ => undefined\nconsole.log(getType(Symbol())); \/\/ => symbol\nconsole.log(getType(BigInt(1234567890123456789012345))); \/\/ => bigint\nconsole.log(getType(function () {})); \/\/ => function\nconsole.log(getType(new Date())); \/\/ => date\nconsole.log(getType(new Map())); \/\/ => map\nconsole.log(getType(new Set())); \/\/ => set \nconsole.log(getType(new RegExp(\"cat\", \"i\"))); \/\/ => regex\n<\/pre>\n
        \n
         \u53c2\u8003 <\/h2>\n
          \n
        • javascript \u6570\u636e\u7c7b\u578b\u548c\u6570\u636e\u7ed3\u6784 – mdn<\/li>\n
        • \u6570\u636e\u7c7b\u578b – javascript.info<\/li>\n
        • \u53c2\u8003\u7c7b\u578b – javascript.info<\/li>\n
        • \u4f1f\u5927\u7684\u524d\u7aef<\/li>\n<\/ul>\n
          \u7ec8\u4e8e\u4ecb\u7ecd\u5b8c\u5566\uff01\u5c0f\u4f19\u4f34\u4eec\uff0c\u8fd9\u7bc7\u5173\u4e8e\u300a\u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f – JavaScript \u6311\u6218\u300b\u7684\u4ecb\u7ecd\u5e94\u8be5\u8ba9\u4f60\u6536\u83b7\u591a\u591a\u4e86\u5427\uff01\u6b22\u8fce\u5927\u5bb6\u6536\u85cf\u6216\u5206\u4eab\u7ed9\u66f4\u591a\u9700\u8981\u5b66\u4e60\u7684\u670b\u53cb\u5427~\u7c73\u4e91\u516c\u4f17\u53f7\u4e5f\u4f1a\u53d1\u5e03\u6587\u7ae0\u76f8\u5173\u77e5\u8bc6\uff0c\u5feb\u6765\u5173\u6ce8\u5427\uff01<\/p>\n
                \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb\u5220\u9664    <\/p>\n
          \n
          <\/dt>\n
          \n   \u7f51\u6613\u4f0f\u7fb2\u643a\u624b\u963f\u91cc\u4e91\u5c55\u793a\u9769\u547d\u6027\u6e38\u620fAI\u5e94\u7528\uff0c\u4e91\u6816\u5927\u4f1a\u5f15\u9886\u6280\u672f\u65b0\u9ad8\u5ea6\uff01\n <\/dd>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"
          \u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f – JavaScript \u6311\u6218 \u6536\u85cf \u672c\u7bc7\u6587\u7ae0\u4e3b\u8981\u662f\u7ed3\u5408\u6211\u4e4b\u524d\u9762\u8bd5\u7684\u5404\u79cd\u7ecf\u5386\u548c\u5b9e\u6218\u5f00\u53d1\u4e2d\u9047\u5230\u7684\u95ee\u9898\u89e3\u51b3\u7ecf\u9a8c\u6574\u7406\u7684\uff0c\u5e0c\u671b\u8fd9\u7bc7\u300a\u7c7b\u578b\u5b9e\u7528\u7a0b\u5e8f – JavaScript \u6311\u6218\u300b\u5bf9\u4f60\u6709\u5f88\u5927\u5e2e\u52a9\uff01\u6b22\u8fce\u6536\u85cf\uff0c\u5206\u4eab\u7ed9\u66f4\u591a\u7684\u9700\u8981\u7684\u670b\u53cb\u5b66\u4e60~ \u4ecb\u7ecd \u68c0\u67e5\u7c7b\u578b\u662f\u65e5\u5e38\u7f16\u7801\u548c\u6280\u672f\u9762\u8bd5\u4e2d javascript \u7684\u5e38\u89c1\u505a\u6cd5\u3002 \u60a8\u53ef\u4ee5\u5728 github \u4e0a\u627e\u5230\u8fd9\u7bc7\u6587\u7ae0\u4e2d\u7684\u6240\u6709\u4ee3\u7801\u3002 \u539f\u59cb\u503c \u5728 javascript \u4e2d\uff0c\u9664 object \u4e4b\u5916\u7684\u6240\u6709\u7c7b\u578b\u90fd\u5b9a\u4e49\u76f4\u63a5\u5728\u8bed\u8a00\u6700\u4f4e\u7ea7\u522b\u8868\u793a\u7684\u4e0d\u53ef\u53d8\u503c\u3002\u6211\u4eec\u5c06\u8fd9\u4e9b\u7c7b\u578b\u7684\u503c\u79f0\u4e3a\u539f\u59cb\u503c\u3002 \u6709 7 \u4e2a\u539f\u59cb\u503c\uff1a \u7a7a \u672a\u5b9a\u4e49 \u5e03\u5c14\u503c \u6570\u5b57 bigint \u5b57\u7b26\u4e32 \u7b26\u53f7 \u9664 null \u4e4b\u5916\u7684\u6240\u6709\u539f\u59cb\u7c7b\u578b\u90fd\u53ef\u4ee5\u901a\u8fc7 typeof \u8fd0\u7b97\u7b26\u8fdb\u884c\u6d4b\u8bd5\u3002 typeof null \u8fd4\u56de\u201cobject\u201d\uff0c\u56e0\u6b64\u5fc5\u987b\u4f7f\u7528 === null \u6765\u6d4b\u8bd5 null\u3002 \u56e0\u6b64\uff0c\u6211\u4eec\u5f97\u5230\u4e86\u7b2c\u4e00\u79cd\u7c7b\u578b\u7684\u6548\u7528\u51fd\u6570\u3002 function isboolean(value) { return typeof value === ‘boolean’; } function […]<\/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-52582","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/52582","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=52582"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/52582\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=52582"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=52582"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=52582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}