{"id":1928,"date":"2025-09-27T01:00:08","date_gmt":"2025-09-26T17:00:08","guid":{"rendered":"https:\/\/womeifei.cn\/?p=1928"},"modified":"2025-09-27T11:54:21","modified_gmt":"2025-09-27T03:54:21","slug":"deepclone-%e6%b7%b1%e6%8b%b7%e8%b4%9d","status":"publish","type":"post","link":"https:\/\/womeifei.cn\/index.php\/2025\/09\/27\/deepclone-%e6%b7%b1%e6%8b%b7%e8%b4%9d\/","title":{"rendered":"DeepClone — \u6df1\u62f7\u8d1d"},"content":{"rendered":"\n

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

\u4e3a\u4ec0\u4e48\u9700\u8981\u5355\u72ec\u5b9e\u73b0\u6df1\u62f7\u8d1d\u51fd\u6570?<\/h2>\n\n\n\n

\u5148\u770b\u4e24\u4e2a\u73b0\u8c61<\/h3>\n\n\n\n
const obj1 = { a: { b: { c: 1, d: 2 } } }\nconst obj2 = obj1\nobj2.a = 1\nconsole.log(obj1)\n\/\/ \u8f93\u51fa{ a: 1 }<\/code><\/pre>\n\n\n\n
const obj1 = { a: { b: { c: 1, d: 2 } } }\nconst obj3 = { ...obj1 }\nobj3.a.b = 1\nconsole.log(obj1)\n\/\/ \u8f93\u51fa{ a: { b: 1 } }<\/code><\/pre>\n\n\n\n
\u6211\u4eec\u6765\u8be6\u7ec6\u770b\u4e00\u4e0b\u7b2c\u4e8c\u6bb5\u4ee3\u7801<\/p>\n\n\n\n
\u5185\u5b58\u5e03\u5c40\u5982\u4e0b:<\/strong><\/p>\n\n\n\n
(\u6808\u5185\u5b58 \u5b58\u653e\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/strong>\u200b\uff08number<\/code>\u3001string<\/code>\u3001boolean<\/code>\u3001null<\/code>\u3001undefined<\/code>\u3001symbol<\/code>\u3001bigint<\/code>\uff09\u548c\u5f15\u7528\u7c7b\u578b\u7684\u6307\u9488\uff08\u5185\u5b58\u5730\u5740\uff09\u200b<\/strong>)<\/p>\n\n\n\n
(\u5806\u5185\u5b58 \u5b58\u653e\u5f15\u7528\u7c7b\u578b\u7684\u5b9e\u9645\u6570\u636e<\/strong>\u200b\uff08\u5982 Object<\/code>\u3001Array<\/code>\u3001Function<\/code>\u7b49\uff09)<\/p>\n\n\n\n
[\u6808\u5185\u5b58]
obj1 \u2192 0x100 (\u5806\u5185\u5b58\u5730\u5740)
obj3 \u2192 0x200 (\u5806\u5185\u5b58\u5730\u5740)<\/p>\n\n\n\n
[\u5806\u5185\u5b58]
0x100: { a \u2192 0x300 }
0x200: { a \u2192 0x300 } \/\/ \u6d45\u62f7\u8d1d\u590d\u5236\u4e86\u5f15\u7528
0x300: { b \u2192 0x400 }
0x400: { c: 1, d: 2 }<\/p>\n\n\n\n
\u56fe\u89e3<\/strong><\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u4fee\u6539\u64cd\u4f5c\u7684\u5f71\u54cd<\/strong><\/p>\n\n\n\n
\u5185\u5b58\u53d8\u5316\u8fc7\u7a0b\uff1a<\/p>\n\n\n\n
    \n
  1. \u901a\u8fc7 obj3.a<\/code>\u627e\u5230 0x300<\/code><\/li>\n\n\n\n
  2. \u4fee\u6539 0x300.b<\/code>\u7684\u503c\u4ece{ c: 1, d: 2 }<\/code> \u5230 1 <\/li>\n<\/ol>\n\n\n\n
    \u4fee\u6539\u540e\u5806\u5185\u5b58<\/strong><\/p>\n\n\n\n
    [\u4fee\u6539\u540e\u5806\u5185\u5b58]\n0x300: 1  \/\/ \u539f\u59cb\u503c\u88ab\u4fee\u6539<\/code><\/pre>\n\n\n\n
    \u6700\u7ec8\u5185\u5b58\u72b6\u6001<\/strong><\/p>\n\n\n\n
    [\u6808\u5185\u5b58]\nobj1 \u2192 0x100\nobj3 \u2192 0x200\n\n[\u5806\u5185\u5b58]\n0x100: { a \u2192 0x300 }\n0x200: { a \u2192 0x300 }\n0x300: { b: 1 }<\/code><\/pre>\n\n\n\n
    1.\u5f15\u7528\u7c7b\u578b\u7684\u7279\u70b9<\/h3>\n\n\n\n
    JavaScript \u4e2d\u7684\u5bf9\u8c61\u662f\u5f15\u7528\u7c7b\u578b\uff0c\u8d4b\u503c\u64cd\u4f5c\u53ea\u662f\u590d\u5236\u5f15\u7528\uff1a<\/p>\n\n\n\n
    const original = { a: 1, b: { c: 2 } };\nconst copy = original; \/\/ \u53ea\u662f\u5f15\u7528\u590d\u5236\n\ncopy.a = 3;\nconsole.log(original.a); \/\/ 3 (\u539f\u5bf9\u8c61\u4e5f\u88ab\u4fee\u6539)<\/code><\/pre>\n\n\n\n
    2.\u5185\u7f6e\u65b9\u6cd5\u65e0\u6cd5\u5b9e\u73b0\u6df1\u62f7\u8d1d<\/h3>\n\n\n\n
      \n
    • Object.assign()<\/code>\u548c\u6269\u5c55\u8fd0\u7b97\u7b26 ...<\/code>\u53ea\u80fd\u6d45\u62f7\u8d1d<\/li>\n\n\n\n
    • JSON.parse(JSON.stringify())<\/code>\u6709\u5c40\u9650\u6027\uff1a<\/li>\n<\/ul>\n\n\n\n
      const obj = { \n  date: new Date(),\n  func: () => console.log('hi'),\n  undef: undefined\n};\n\nconst jsonCopy = JSON.parse(JSON.stringify(obj));\n\/\/ { date: \"2023-05-01T12:00:00.000Z\" } \n\/\/ \u51fd\u6570\u548cundefined\u4e22\u5931\uff0cDate\u5bf9\u8c61\u8f6c\u4e3a\u5b57\u7b26\u4e32<\/code><\/pre>\n\n\n\n
      3.\u7279\u6b8a\u5bf9\u8c61\u7c7b\u578b\u7684\u5904\u7406<\/h3>\n\n\n\n
      \u9700\u8981\u5355\u72ec\u5904\u7406\u4ee5\u4e0b\u7c7b\u578b\uff1a<\/p>\n\n\n\n
        \n
      • Date<\/code>\u5bf9\u8c61<\/li>\n\n\n\n
      • RegExp<\/code>\u5bf9\u8c61<\/li>\n\n\n\n
      • Map<\/code>\/Set<\/code>\u96c6\u5408<\/li>\n\n\n\n
      • \u51fd\u6570 (\u901a\u5e38\u9009\u62e9\u4e0d\u62f7\u8d1d)<\/li>\n\n\n\n
      • \u5faa\u73af\u5f15\u7528 (\u5bf9\u8c61\u5f15\u7528\u81ea\u8eab)<\/li>\n<\/ul>\n\n\n\n
        4.\u6027\u80fd\u4e0e\u5b89\u5168\u8003\u8651<\/h3>\n\n\n\n
          \n
        • \u6df1\u62f7\u8d1d\u662f\u9012\u5f52\u64cd\u4f5c\uff0c\u9700\u8981\u6027\u80fd\u4f18\u5316<\/li>\n\n\n\n
        • \u9632\u6b62\u62f7\u8d1d\u8fc7\u7a0b\u4e2d\u539f\u578b\u94fe\u6c61\u67d3<\/li>\n\n\n\n
        • \u907f\u514d\u610f\u5916\u4fee\u6539\u5171\u4eab\u7684\u5f15\u7528\u6570\u636e<\/li>\n<\/ul>\n\n\n\n
          \u600e\u4e48\u5b9e\u73b0? \u5148\u522b\u60f3\u592a\u591a<\/h2>\n\n\n\n
          \u5148\u522b\u60f3\u592a\u591a \u601d\u8def\u5f88\u7b80\u5355 \u5148\u8bbe\u7f6e\u4e2a\u65b0\u7684\u7a7a\u5bf9\u8c61\u7528\u4e8e\u62f7\u8d1d \u518d\u904d\u5386\u539f\u5bf9\u8c61\u7684\u6bcf\u4e2akey \u5982\u679ckey\u5bf9\u5e94\u7684value \u662f\u57fa\u7840\u7c7b\u578b\u90a3\u5c31\u76f4\u63a5\u8d4b\u503c\u7ed9\u7a7a\u5bf9\u8c61\u5373\u53ef \u5982\u679c\u662f\u5bf9\u8c61\u7c7b\u578b\u90a3\u5c31\u7ee7\u7eed\u904d\u5386\u8fd9\u4e2a\u5bf9\u8c61 —> \u8fd9\u91cc\u5f88\u660e\u663e\u8981\u9012\u5f52\u8c03\u7528\u4e86<\/p>\n\n\n\n
          \u4ee3\u7801\u5982\u4e0b<\/p>\n\n\n\n
          \"\"<\/div><\/figure>\n\n\n\n
          \u8f93\u51fa:<\/p>\n\n\n\n
          { a: { b: { c: 1, d: 2 } } }
          { a: 1 }<\/p>\n\n\n\n
          \u8bf4\u660e\u5df2\u7ecf\u6210\u529f\u5b8c\u6210\u6df1\u62f7\u8d1d<\/p>\n\n\n\n
          \u60f3\u591a\u4e00\u70b9! \u4ee3\u7801\u4e0d\u592a\u4e25\u8c28<\/h2>\n\n\n\n
          \u6f5c\u5728\u4ee5\u4e0b\u95ee\u9898<\/strong><\/p>\n\n\n\n
          1.\u65e0\u6cd5\u5904\u7406\u6570\u7ec4<\/h3>\n\n\n\n
          \u5982\u679c obj<\/code>\u662f\u6570\u7ec4\uff0c\u4f60\u7684\u4ee3\u7801\u4f1a\u9519\u8bef\u5730\u628a\u5b83\u8f6c\u6210\u666e\u901a\u5bf9\u8c61\uff1a<\/p>\n\n\n\n
          const arr = [1, 2, { a: 3 }];\nconst clonedArr = deepClone(arr);\nconsole.log(clonedArr); \/\/ \u8f93\u51fa\uff1a{ 0: 1, 1: 2, 2: { a: 3 } }\uff08\u4e0d\u662f\u6570\u7ec4\uff01\uff09<\/code><\/pre>\n\n\n\n
          \u4fee\u590d\u65b9\u6cd5:<\/strong><\/p>\n\n\n\n
          const result = Array.isArray(obj) ? [] : {};<\/code><\/pre>\n\n\n\n
          2.\u65e0\u6cd5\u5904\u7406\u5faa\u73af\u5bf9\u8c61<\/h3>\n\n\n\n
          \u5982\u679c\u5bf9\u8c61\u6709\u5faa\u73af\u5f15\u7528\uff08\u5982 obj.self = obj<\/code>\uff09\uff0c\u4f1a\u8fdb\u5165\u65e0\u9650\u9012\u5f52\u5bfc\u81f4\u6808\u6ea2\u51fa\uff1a<\/p>\n\n\n\n
          \u5982\u4e0a\u56fe \u7b2c10\u884c\u4ee3\u7801\u4f1a\u65e0\u9650\u9012\u5f52\u6267\u884c<\/p>\n\n\n\n
          const obj = { a: 1 };\nobj.self = obj; \/\/ \u5faa\u73af\u5f15\u7528\ndeepClone(obj); \/\/ \u62a5\u9519\uff1aMaximum call stack size exceeded<\/code><\/pre>\n\n\n\n
          \u4fee\u590d\u65b9\u6cd5:\u4f7f\u7528 WeakMap<\/code>\u7f13\u5b58\u5df2\u62f7\u8d1d\u7684\u5bf9\u8c61\uff1a<\/strong><\/p>\n\n\n\n
          \u7b80\u5355\u4ecb\u7ecd\u4e00\u4e0bweakMap:<\/strong><\/p>\n\n\n\n
          WeakMap<\/strong>\u200b \u662f JavaScript \u4e2d\u7684\u4e00\u79cd\u7279\u6b8a\u952e\u503c\u5bf9\u96c6\u5408\uff0c\u4e0e\u666e\u901a Map<\/code>\u7c7b\u4f3c\uff0c\u4f46\u6709\u4ee5\u4e0b\u5173\u952e\u533a\u522b\uff1a\u200b<\/p>\n\n\n\n
          \u200b\u952e\u5fc5\u987b\u662f\u5bf9\u8c61<\/strong>\u200b\uff08\u4e0d\u80fd\u662f\u57fa\u672c\u7c7b\u578b\uff1anumber<\/code>\u3001string<\/code>\u7b49\uff09<\/p>\n\n\n\n
          const deepClone = (obj, cache = new WeakMap()) => {\n    if (cache.has(obj)) return cache.get(obj); \/\/ \u5982\u679c\u5df2\u62f7\u8d1d\u8fc7\uff0c\u76f4\u63a5\u8fd4\u56de\n    const result = Array.isArray(obj) ? [] : {};\n    cache.set(obj, result); \/\/ \u7f13\u5b58\u5f53\u524d\u5bf9\u8c61\n    \/\/ ...\u5176\u4f59\u903b\u8f91\u4e0d\u53d8\n};<\/code><\/pre>\n\n\n\n
          3.\u65e0\u6cd5\u5904\u7406\u7279\u6b8a\u5bf9\u8c61\uff08\u5982RegExp, Date, Set, Map\uff09\u200b<\/h3>\n\n\n\n
          \u5982\u679c\u5bf9\u8c61\u5305\u542b Date<\/code>\u3001RegExp<\/code>\u7b49\u7279\u6b8a\u5bf9\u8c61\uff0c\u4f1a\u88ab\u76f4\u63a5\u5f53\u4f5c\u666e\u901a\u5bf9\u8c61\u62f7\u8d1d\uff1a<\/p>\n\n\n\n
          const obj = { date: new Date(), regex: \/abc\/g };\nconst cloned = deepClone(obj);\nconsole.log(cloned.date); \/\/ \u8f93\u51fa\uff1a\u666e\u901a\u5bf9\u8c61 { ... }\uff0c\u800c\u4e0d\u662f Date \u5b9e\u4f8b<\/code><\/pre>\n\n\n\n
          \u4fee\u590d\u65b9\u6cd5:\u7279\u6b8a\u5904\u7406\u8fd9\u4e9b\u7c7b\u578b<\/strong><\/p>\n\n\n\n
          if (obj instanceof Date) return new Date(obj);\nif (obj instanceof RegExp) return new RegExp(obj);<\/code><\/pre>\n\n\n\n
          \u6539\u8fdb\u540e\u7684\u6700\u4f73\u5b9e\u8df5<\/h2>\n\n\n\n
          function deepClone(obj, cache = new WeakMap()) {\n    \/\/ \u57fa\u672c\u7c7b\u578b\u76f4\u63a5\u8fd4\u56de\n    if (obj === null || typeof obj !== 'object') {\n        return obj;\n    }\n\n    \/\/ \u5904\u7406\u5faa\u73af\u5f15\u7528\n    if (cache.has(obj)) {\n        return cache.get(obj);\n    }\n\n    \/\/ \u5904\u7406 Date \u5bf9\u8c61\n    \/\/ instanceof\uff1aJavaScript \u8fd0\u7b97\u7b26\uff0c\u7528\u4e8e\u68c0\u67e5\u5de6\u4fa7\u5bf9\u8c61\u662f\u5426\u662f\u53f3\u4fa7\u6784\u9020\u51fd\u6570\u7684\u5b9e\u4f8b\n    if (obj instanceof Date) {\n        return new Date(obj);\n    }\n\n    \/\/ \u5904\u7406 RegExp \u5bf9\u8c61\n    if (obj instanceof RegExp) {\n        return new RegExp(obj);\n    }\n\n    \/\/ \u521d\u59cb\u5316\u514b\u9686\u5bf9\u8c61\uff08\u6570\u7ec4 or \u666e\u901a\u5bf9\u8c61\uff09\n    const clone = Array.isArray(obj) ? [] : {};\n\n    \/\/ \u7f13\u5b58\u5f53\u524d\u5bf9\u8c61\uff0c\u9632\u6b62\u5faa\u73af\u5f15\u7528\n    cache.set(obj, clone);\n\n    \/\/ \u514b\u9686\u666e\u901a\u5c5e\u6027\n    for (const key in obj) {\n        if (obj.hasOwnProperty(key)) {\n            clone[key] = deepClone(obj[key], cache);\n        }\n    }\n\n\n    return clone;\n}<\/code><\/pre>\n\n\n\n
          \u6d4b\u8bd5\u7528\u4f8b<\/strong><\/p>\n\n\n\n
          const obj = {\n    a: 1,\n    b: { c: 2 },\n    d: new Date(),\n    e: \/regex\/g,\n    f: [1, 2, { g: 3 }]\n};\nobj.self = obj; \/\/ \u5faa\u73af\u5f15\u7528\n\nconst cloned = deepClone(obj);\nconsole.log(cloned);<\/code><\/pre>\n\n\n\n
          \u8f93\u51fa<\/strong><\/p>\n\n\n\n
          {\n    a: 1,\n    b: { c: 2 },\n    d: 2025-09-27T00:00:00.000Z, \/\/ Date \u7c7b\u578b\u4fdd\u7559\n    e: \/regex\/g,                  \/\/ RegExp \u7c7b\u578b\u4fdd\u7559\n    f: [1, 2, { g: 3 }],          \/\/ \u6570\u7ec4\u548c\u5d4c\u5957\u5bf9\u8c61\u6b63\u786e\u514b\u9686\n    self: [Circular]              \/\/ \u5faa\u73af\u5f15\u7528\u88ab\u6b63\u786e\u5904\u7406\n}<\/code><\/pre>\n\n\n\n
          <\/p>\n","protected":false},"excerpt":{"rendered":"
          \u4e3a\u4ec0\u4e48\u9700\u8981\u5355\u72ec\u5b9e\u73b0\u6df1\u62f7\u8d1d\u51fd\u6570? \u5148\u770b\u4e24\u4e2a\u73b0\u8c61 \u6211\u4eec\u6765\u8be6\u7ec6\u770b\u4e00\u4e0b\u7b2c\u4e8c\u6bb5\u4ee3\u7801 \u5185\u5b58\u5e03\u5c40\u5982\u4e0b: (\u6808\u5185\u5b58 \u5b58\u653e\u57fa\u672c\u6570 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10,1,46],"tags":[],"class_list":["post-1928","post","type-post","status-publish","format-standard","hentry","category-javascript","category-1","category-46"],"_links":{"self":[{"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/posts\/1928","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/comments?post=1928"}],"version-history":[{"count":9,"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/posts\/1928\/revisions"}],"predecessor-version":[{"id":1940,"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/posts\/1928\/revisions\/1940"}],"wp:attachment":[{"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/media?parent=1928"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/categories?post=1928"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/womeifei.cn\/index.php\/wp-json\/wp\/v2\/tags?post=1928"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}