{"id":10064,"date":"2021-08-15T12:40:49","date_gmt":"2021-08-15T04:40:49","guid":{"rendered":"https:\/\/www.zhangxinxu.com\/wordpress\/?p=10064"},"modified":"2021-08-15T21:43:15","modified_gmt":"2021-08-15T13:43:15","slug":"js-weakmap-es6","status":"publish","type":"post","link":"https:\/\/www.zhangxinxu.com\/wordpress\/2021\/08\/js-weakmap-es6\/","title":{"rendered":"JS WeakMap\u5e94\u8be5\u4ec0\u4e48\u65f6\u5019\u4f7f\u7528"},"content":{"rendered":"<p>by <a href=\"https:\/\/www.zhangxinxu.com\/\">zhangxinxu<\/a> from <a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/?p=10064\">https:\/\/www.zhangxinxu.com\/wordpress\/?p=10064<\/a> \u946b\u7a7a\u95f4-\u946b\u751f\u6d3b<br \/>\n\u672c\u6587\u6b22\u8fce\u5206\u4eab\u4e0e\u805a\u5408\uff0c\u5168\u6587\u8f6c\u8f7d\u5c31\u4e0d\u5fc5\u4e86\uff0c\u5c0a\u91cd\u7248\u6743\uff0c\u5708\u5b50\u5c31\u8fd9\u4e48\u5927\uff0c\u82e5\u6025\u7528\u53ef\u4ee5\u8054\u7cfb\u6388\u6743\u3002<\/p>\n<p><script>window.wxShareImgUrl = 'https:\/\/www.zhangxinxu.com\/study\/image\/share\/202108-weakmap.png';<\/script><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202108\/weakmap-cover.png\" width=\"481\" height=\"340\" alt=\"\u7ea2\u6885\u8461\u8404\u5360\u4f4d\u56fe\" class=\"alignright clip thumb size-medium\" \/><\/p>\n<h3>\u4e00\u3001\u4ece\u54ea\u91cc\u5f00\u59cb\u5462\uff1f<\/h3>\n<p>\u7b97\u4e86\uff0c\u8fd8\u662f\u5148\u8bf4\u7ed3\u8bba\u5427\u3002<\/p>\n<h3>\u4e8c\u3001WeakMap\u4ec0\u4e48\u65f6\u5019\u7528\uff1f<\/h3>\n<p>\u9996\u5148\uff0c\u5927\u5bb6\u8981\u660e\u767d\uff0c\u5c31\u7b97\u6ca1\u6709 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id=\"img\" src=\"https:\/\/bookcover.yuewen.com\/qdbimg\/349573\/1027030348\/180\"&gt;<\/pre>\n<p>\u7136\u540e\uff0c\u9700\u8981\u5220\u9664\u6b64DOM\u5143\u7d20\uff0c\u5c0f\u660e\u662f\u8fd9\u4e48\u5904\u7406\u7684\uff1a<\/p>\n<pre>var eleImage = document.getElementById('img');\r\neleImage.remove();<\/pre>\n<p>\u8fd9\u4e2a\u5904\u7406\u6709\u6ca1\u6709\u4ec0\u4e48\u95ee\u9898\uff1f<\/p>\n<p>\u4ece\u6548\u679c\u4e0a\u6765\u770b\uff0c\u5b8c\u5168\u89e3\u51b3\u4e86\u9700\u6c42\u3002<\/p>\n<p>\u4f46\u662f\u5b9e\u9645\u4e0a\uff0c\u867d\u7136\u9875\u9762\u4e2d\u7684\u56fe\u7247\u5143\u7d20\u5220\u9664\u4e86\uff0c\u4f46\u662f\u5185\u5b58\u4e2d\u7684\u8fd9\u4e2aDOM\u5bf9\u8c61\u4f9d\u7136\u5b58\u5728\u7684\u3002<\/p>\n<p>\u6211\u4eec\u4e0d\u59a8\u8fd9\u6837\u6d4b\u8bd5\u4e0b\uff1a<\/p>\n<pre>var eleImage = document.getElementById('img');\r\neleImage.remove();\r\n\r\nsetTimeout(() => {\r\n  document.body.append(eleImage);\r\n}, 2000);<\/pre>\n<p>\u5c31\u4f1a\u770b\u5230\u56fe\u7247\u88ab\u5220\u9664\u4e86\uff08\u5982\u4e0bGIF\u5f55\u5c4f\uff09\uff0c\u7136\u540e\u8fc7\u4e862\u79d2\u949f\u53c8\u51fa\u73b0\u5728\u4e86\u9875\u9762\u4e0a\uff0c\u56e0\u4e3aeleImage\u8fd8\u5728\u5185\u5b58\u4e2d\uff0c\u5e76\u672a\u6e05\u9664\uff0c\u4e0d\u4f1a\u88ab\u56de\u6536\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202108\/image-append.gif\" width=\"241\" height=\"282\" alt=\"\u5220\u9664\u540e2\u79d2\u53c8\u51fa\u73b0\" class=\"alignnone size-medium\" \/><\/p>\n<p>\u6240\u4ee5\uff0c\u5982\u679c\u786e\u5b9aeleImage\u4e0d\u518d\u9700\u8981\uff0c\u9700\u8981\u591a\u6267\u884c\u4e00\u53e5\uff0c\u540c\u65f6\u8bbe\u4e3a null\u3002<\/p>\n<pre>var eleImage = document.getElementById('img');\r\neleImage.remove();\r\neleImage = null;<\/pre>\n<p>\u8fd9\u6837\uff0cJS\u5728\u6267\u884c\u5783\u573e\u56de\u6536\u7684\u65f6\u5019\uff0c\u5c31\u4f1a\u628aeleImage\u8fd9\u4e2a\u5783\u573e\u6536\u56de\uff0c\u91ca\u653e\u5185\u5b58\u3002<\/p>\n<p>\u5927\u5bb6\u53ef\u4ee5\u770b\u770b\u81ea\u5df1\u662f\u4e0d\u5173\u5fc3\u5185\u5b58\u7684\u90a3\u7c7bJS\u5f00\u53d1\uff0c\u8fd8\u662f\u4f1a\u6ce8\u610f\u91ca\u653e\u4e0d\u9700\u8981\u7684\u5185\u5b58\u7684JS\u5f00\u53d1\u3002<\/p>\n<p>OK\uff0c\u4e8b\u60c5\u8fd8\u6ca1\u5b8c\uff0c\u6709\u65f6\u5019\uff0c\u8bbe\u7f6eeleImage\u4e3a<code>null<\/code>\uff0c\u5e76\u4e0d\u80fd\u771f\u6b63\u56de\u6536\u5185\u5b58\u3002<\/p>\n<p>\u4f8b\u5982\u5b9e\u9645\u5f00\u53d1\uff0c\u6709\u65f6\u5019\u9700\u8981\u8bb0\u4f4f\u521d\u59cb\u7684outerHTML\u5b57\u7b26\uff0c\u65b9\u4fbf\u8fd8\u539f\u3002\u4e3a\u4e86\u548c\u539f\u59cbDOM\u4ea7\u751f\u5173\u8054\uff0c\u6709\u4e9b\u5f00\u53d1\u5c31\u628aDOM\u5143\u7d20\u548couterHTML\u5b57\u7b26\u4e32\u653e\u5728\u540c\u4e00\u4e2a\u6570\u7ec4\u4e2d\u8fdb\u884c\u7ba1\u7406\uff1a<\/p>\n<pre>var eleImage = document.getElementById('img');\r\nvar storage = {\r\n    arrDom: [eleImage, eleImage.outerHTML]\r\n};\r\neleImage.remove();\r\neleImage = null;<\/pre>\n<p>\u6b64\u65f6\uff0celeImage\u8fd9\u4e2aDOM\u5bf9\u8c61\u5176\u5b9e\u8fd8\u5728\u5185\u5b58\u4e2d\u3002\u56e0\u4e3a eleImage \u88ab <code>storage.arrDom<\/code> \u5f15\u7528\u4e86\uff0c\u5373\u4f7feleImage\u8bbe\u4e3a<code>null<\/code>\u4e5f\u65e0\u6cd5\u5c06\u5185\u5b58\u5f7b\u5e95\u91ca\u653e\u3002<\/p>\n<p>\u6d4b\u8bd5\u4e0b\uff1a<\/p>\n<pre>var eleImage = document.getElementById('img');\r\nvar storage = {\r\n    arrDom: [eleImage, eleImage.outerHTML]\r\n};\r\neleImage.remove();\r\neleImage = null;\r\n\r\nsetTimeout(() => {\r\n  document.body.append(storage.arrDom[0]);\r\n}, 2000);<\/pre>\n<p>\u540c\u6837\u53ef\u4ee5\u770b\u5230\uff0c\u56fe\u7247\u88ab\u5220\u9664\u540e\uff0c2\u79d2\u540e\u53c8\u51fa\u73b0\u4e86\u3002<\/p>\n<p>\u8fd9\u4e2a\u8fd8\u662f\u770b\u5b9e\u65f6\u6548\u679c\u5427\u3002<\/p>\n<p>\u70b9\u51fb\u540e\u9762\u7684\u6309\u94ae\u67e5\u770b\u6548\u679c\uff1a<button id=\"wmpFBtn\">\u70b9\u51fb\u6211\u6267\u884cremove\u518d\u5b9a\u65f6\u663e\u793a~\u55b5\u513f~<\/button><\/p>\n<div id=\"boxXXX\" style=\"height:260px;width:280px;padding:8px;border:1px solid gray;\"><img decoding=\"async\" id=\"imgXX\" src=\"https:\/\/bookcover.yuewen.com\/qdbimg\/349573\/1027030348\/180\"><\/div>\n<p><script>\n(function () {\nvar button = document.getElementById('wmpFBtn');\nvar eleImage = document.getElementById('imgXX');\nvar box = document.getElementById('boxXXX');\nvar storage = {arrDom: [eleImage, eleImage.outerHTML]};\nif (button) {\nbutton.onclick = function () {\neleImage.remove();\neleImage = null;\nsetTimeout(function() {box.appendChild(storage.arrDom[0]);}, 2000);\n}\n}\n})();\n<\/script><\/p>\n<p>\u6b64\u65f6\uff0c\u8981\u60f3\u5b8c\u5168\u628a\u56fe\u50cf\u7684\u5185\u5b58\u91ca\u653e\uff0c\u8fd8\u9700\u8981\u6267\u884c\u4e0b\u9762\u8fd9\u884c\uff1a<\/p>\n<pre>storage.arrDom[0] = null;<\/pre>\n<p>\u5927\u5bb6\u8bd5\u60f3\u4e0b\uff0c\u5982\u679c\u662f\u4f60\uff0c\u53ef\u4ee5\u91ca\u653e\u5185\u5b58\u505a\u5230\u8fd9\u4e00\u6b65\u5417\uff1f\u5982\u679c\u53ef\u4ee5\u505a\u5230\uff0c\u90a3\u4f60\u5c31\u53ef\u4ee5\u5f52\u7c7b\u4e3a\u8d44\u6df1\u7684JS\u524d\u7aef\u5f00\u53d1\u90a3\u4e00\u7c7b\u4e86\u3002<\/p>\n<p>\u4f46\u662f\uff0c\u7eaf\u9760\u6280\u672f\u624b\u6bb5\uff0c\u4eba\u5de5\u8bc6\u522b\u54ea\u4e9b\u5730\u65b9\u7684\u5185\u5b58\u8981\u91ca\u653e\uff0c\u5b9e\u5728\u662f\u592a\u7d2f\u4e86\u3002\u5c31\u7b97\u61c2\u884c\u7684\u4eba\u6709\u65f6\u5019\u5acc\u9ebb\u70e6\uff0c\u90fd\u61d2\u5f97\u53bb\u7ba1\u7406\uff0c\u90a3\u6709\u6ca1\u6709\u4ec0\u4e48\u624b\u6bb5\uff0c\u6211\u53ea\u8981\u53d8\u91cf\u8bbe\u4e3anull\uff0c\u6240\u6709\u6709\u5f15\u7528\u7684\u5730\u65b9\u7684\u5185\u5b58\u90fd\u81ea\u52a8\u91ca\u653e\u5462\uff1f<\/p>\n<p>\u8fd9\u5c31\u53ef\u4ee5\u8003\u8651\u4f7f\u7528WeakMap\u4e86\u3002<\/p>\n<p><span class=\"hidden\">\/\/zxx: \u5982\u679c\u4f60\u770b\u5230\u8fd9\u6bb5\u6587\u5b57\uff0c\u8bf4\u660e\u4f60\u73b0\u5728\u8bbf\u95ee\u662f\u4f53\u9a8c\u7cdf\u7cd5\u7684\u5783\u573e\u76d7\u7248\u7f51\u7ad9\uff0c\u4f60\u53ef\u4ee5\u8bbf\u95ee\u539f\u6587\u83b7\u5f97\u5f88\u597d\u7684\u4f53\u9a8c\uff1ahttps:\/\/www.zhangxinxu.com\/wordpress\/?p=10064\uff08\u4f5c\u8005\u5f20\u946b\u65ed\uff09<\/span><\/p>\n<h4>\u4f7f\u7528\u573a\u666f<\/h4>\n<p>\u4e0a\u9762\u7684\u4f8b\u5b50\uff0c\u5982\u679c\u4f7f\u7528WeakMap\u5b9e\u73b0\u56de\u662f\u600e\u6837\u7684\u5462\uff1f<\/p>\n<p>\u4ee3\u7801\u8bf4\u8bdd\uff1a<\/p>\n<pre>var eleImage = document.getElementById('img');\r\nvar storeMap = new WeakMap();\r\nstoreMap.set(eleImage, eleImage.outerHTML);\r\neleImage.remove();\r\neleImage = null;<\/pre>\n<p>\u540c\u6837\u662f\u7f13\u5b58\u56fe\u7247\u7684outerHTML\u6570\u636e\uff0c\u4f46\u662f\u8fd9\u91cc\u4f7f\u7528\u4e86 WeakMap \u5bf9\u8c61\uff0c\u5c06 eleImage \u4f5c\u4e3a\u4e00\u4e2a\u5f31\u952e\uff0c\u8fd9\u6837\uff0celeImage\u4e00\u65e6\u8bbe\u7f6e\u4e3a null\uff0c\u6240\u6709\u76f8\u5173\u7684\u6570\u636e\u90fd\u4f1a\u88ab\u91ca\u653e\u3002<\/p>\n<p>\u7a76\u7adf\u5185\u5b58\u91ca\u653e\u6ca1\u6709\uff0c\u4e0a\u9762\u7684\u4f8b\u5b50\u4e0d\u597d\u6d4b\u8bd5\uff0c\u4e00\u662f\u8981\u501f\u52a9\u5de5\u5177\uff0c\u4e8c\u662f\u5185\u5b58\u53d8\u5316\u5f88\u5c0f\uff0c\u770b\u4e0d\u51fa\u6765\u3002<\/p>\n<p><strong>\u66f4\u65b0\u4e8e\u5f53\u65e5<\/strong><br \/>\n\u7ecf\u8fc7\u8bc4\u8bba\u53cd\u9988\uff0cFinalizationRegistry\u662f\u53ef\u4ee5\u68c0\u6d4b\u5783\u573e\u56de\u6536\u7684\u6267\u884c\uff0c\u5e76\u89e6\u53d1\u76f8\u5e94\u7684\u56de\u8c03\u7684\u3002<\/p>\n<p>\u4e0d\u8fc7\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528Map\u5bf9\u8c61\u5bf9\u6bd4\u4e0b\uff0c\u5982\u679c\u662fMap\u5bf9\u8c61\uff0c<code>eleImage<\/code>\u4f5c\u4e3a\u952e\uff0c\u90a3\u5c31\u662f\u5f3a\u5f15\u7528\uff0c\u662f\u4e00\u76f4\u5728\u5185\u5b58\u4e2d\u7684\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre>var eleImage = document.getElementById('img');\r\nvar storeMap = new Map();\r\nstoreMap.set(eleImage, eleImage.outerHTML);\r\neleImage.remove();\r\neleImage = null;\r\n\r\nsetTimeout(() => {\r\n  document.body.append(storeMap.keys().next().value);\r\n}, 2000);<\/pre>\n<p>\u53ef\u4ee5\u770b\u5230\uff0c\u867d\u7136eleImage remove\u6389\u4e86\uff0c\u8fd8\u8bbe\u4e3a\u4e86null\uff0c\u4f46\u662f\u4f9d\u7136\u5728\u5185\u5b58\u4e2d\uff0c\u53ef\u4ee5append\u5230\u9875\u9762\u4e2d\u3002<\/p>\n<p>\u6839\u636e\u4e0a\u9762\u7684\u5206\u6790\u548c\u63cf\u8ff0\uff0c\u6211\u4eec\u53ef\u4ee5\u5f97\u51fa\u4e0b\u9762\u7684\u7ed3\u8bba\u3002<\/p>\n<h4>\u7ed3\u8bba<\/h4>\n<p>\u5f53\u6211\u4eec\u9700\u8981\u5728\u67d0\u4e2a\u5bf9\u8c61\u4e0a\u4e34\u65f6\u5b58\u653e\u6570\u636e\u7684\u65f6\u5019\uff0c\u8bf7\u4f7f\u7528WeakMap\uff0c\u5c24\u5176\u5bf9\u4e8eJS\u7406\u89e3\u4e0d\u662f\u5f88\u6df1\u523b\u7684\u5f00\u53d1\u4eba\u5458\uff0c\u66f4\u662f\u5982\u6b64\uff0c\u56e0\u4e3a\u7701\u5fc3\uff0c\u4e0d\u8981\u5173\u5fc3\u7ecf\u5e38\u6302\u5728\u5634\u8fb9\u7684\u201c\u5185\u5b58\u6cc4\u9732\u201d\u95ee\u9898\u3002<\/p>\n<p>\u56e0\u4e3a\u5230\u65f6\u5019\u53ea\u9700\u8981\u5220\u9664\u8be5\u5bf9\u8c61\uff0c\u6240\u6709\u76f8\u5173\u7684\u5f15\u7528\u548c\u5173\u8054\u7684\u5185\u5b58\u90fd\u4f1a\u88ab\u91ca\u653e\u3002<\/p>\n<p>\u4e5f\u5c31\u662f\uff0c\u867d\u7136\u6211\u770b\u4e0d\u61c2\u4ee3\u7801\u662f\u600e\u4e48\u6267\u884c\u7684\uff0c\u4f46\u662f\u6211\u8fd9\u4e48\u5199\u7684\uff0c\u6027\u80fd\u5c31\u662f\u597d\uff0c\u903c\u683c\u5c31\u662f\u9ad8\uff01<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202108\/2021-08-15_104552.jpg\" width=\"320\" height=\"212\" alt=\"\u770b\u4e0d\u61c2\" class=\"alignnone size-medium\" \/><\/p>\n<h3>\u4e09\u3001\u56de\u5230WeakMap\u8bed\u6cd5\u672c\u8eab<\/h3>\n<p>\u8bf4\u4e86\u8fd9\u4e48\u591a\uff0c\u662f\u65f6\u5019\u4ecb\u7ecd WeakMap \u8bed\u6cd5\u7684\u771f\u8eab\u4e86\u3002<\/p>\n<h4>\u8bed\u6cd5<\/h4>\n<pre>let myWm = new WeakMap()<\/pre>\n<p>\u6b64\u65f6\uff0cmyWm\u5c31\u662f\u4e00\u4e2a\u65b0\u7684WeakMap\u5bf9\u8c61\uff0c\u5305\u62ec\u4e86\u4e0b\u9762\u8fd9\u4e9b\u65b9\u6cd5\uff1a<\/p>\n<pre><span style=\"color:green;\">\/\/ \u5220\u9664\u952e<\/span>\r\nmyWm.delete(key);\r\n<span style=\"color:green;\">\/\/ \u8bbe\u7f6e\u952e\u548c\u503c<\/span>\r\nmyWm.set(key, value);\r\n<span style=\"color:green;\">\/\/ \u662f\u5426\u5305\u542b\u67d0\u952e<\/span>\r\nmyWm.has(key);\r\n<span style=\"color:green;\">\/\/ \u83b7\u53d6\u952e\u5bf9\u5e94\u7684\u503c<\/span>\r\nmyWm.get(key);<\/pre>\n<h4>\u8bf4\u660e<\/h4>\n<ol>\n<li>key\u53ea\u80fd\u662f\u5bf9\u8c61\uff0c\u4e0d\u80fd\u662f\u539f\u59cb\u6570\u636e\u7c7b\u578b\uff08\u5b57\u7b26\u4e32\u3001\u6570\u5b57\u3001true\u6216false\uff0cnull\uff0cundefined\uff0csymbol\u7b49\u7c7b\u578b\uff09<\/li>\n<li>WeakMap\u4e2d\u7684\u952e\u662f\u65e0\u6cd5\u679a\u4e3e\u7684<\/li>\n<\/ol>\n<p><strong>key\u53ea\u80fd\u662f\u5bf9\u8c61<\/strong><\/p>\n<p>\u4e0b\u9762\u7684\u7528\u6cd5\u90fd\u662f\u53ef\u4ee5\u7684\uff1a<\/p>\n<pre>myWm.set([], 1);\r\nmyWm.set(new Date(), '\u946b\u7a7a\u95f4');\r\nmyWm.set(()=&gt;{}, 1);\r\nmyWm.set(document.createElement('by-zhangxinxu'), 1);<\/pre>\n<p>\u4f46\u662f\u5982\u679ckey\u4e0d\u662f\u5bf9\u8c61\uff0c\u800c\u662f\u5b57\u7b26\u4e32\u4e4b\u7c7b\u7684\u57fa\u672c\u7c7b\u578b\uff0c\u5c31\u4f1a\u62a5\u9519\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><span style=\"color:green;\">\/\/ \u4f1a\u62a5\u9519<\/span>\r\nmyWm.set('css\u65b0\u4e16\u754c', true);<\/pre>\n<p>\u6b64\u65f6\u4f1a\u62a5\u4e0b\u9762\u7684\u9519\u8bef\uff1a<\/p>\n<blockquote><p>&#8220;TypeError: Invalid value used as weak map key<\/p><\/blockquote>\n<p>\u56e0\u6b64WeakMap\u9002\u5408\u7528\u5728\u5728\u5bf9\u8c61\u4e0a\u4e34\u65f6\u7f13\u5b58\u6570\u636e\u7684\u573a\u666f\u3002<\/p>\n<p><strong>key\u65e0\u6cd5\u679a\u4e3e<\/strong><\/p>\n<p>\u4e0d\u540c\u4e8eMap\u5bf9\u8c61\uff0cMap\u5bf9\u8c61\u662f\u53ef\u4ee5\u679a\u4e3e\u7684\uff0c\u6709<code>keys()<\/code>\u3001<code>values()<\/code>\u3001<code>entries()<\/code>\u65b9\u6cd5\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528<code>forEach<\/code>\u904d\u5386\u3002<\/p>\n<p>\u4f46\u662fWeakMap\u65e0\u6cd5\u679a\u4e3e\uff0cWeakMap\u7684\u8fd9\u4e2a\u7279\u6027\u4e5f\u53ef\u4ee5\u7528\u6765\u6a21\u62df\u79c1\u6709\u5c5e\u6027\u3002<\/p>\n<pre>const myWm = new WeakMap();\r\nclass Fish {\r\n    constructor(name) {\r\n        myWm.set(this, { \r\n            _fishbone: ['\u8349\u9c7c', '\u9cab\u9c7c', '\u9752\u9c7c', '\u9ca4\u9c7c', '\u9ca2\u9c7c', '\u9cd9\u9c7c', '\u9cca\u9c7c', '\u7fd8\u5634', '\u9910\u6761'],\r\n        });\r\n        this.name = name;\r\n    }\r\n\r\n    isBone() {\r\n        return myWm.get(this)._fishbone.includes(this.name);\r\n    }\r\n}\r\n\r\n<span style=\"color:green;\">\/\/ \u6d4b\u8bd5\uff0c\u4e70\u4e86\u4e24\u6761\u9c7c<\/span>\r\nlet fish1 = new Fish('\u8349\u9c7c');\r\nlet fish2 = new Fish('\u56de\u9c7c');\r\n\r\n<span style=\"color:green;\">\/\/ \u8fd4\u56de true\uff0c\u6709\u523a<\/span>\r\nconsole.log(fish1.isBone());\r\n<span style=\"color:green;\">\/\/ \u8fd4\u56de false\uff0c\u6ca1\u6709\u808c\u95f4\u523a<\/span>\r\nconsole.log(fish2.isBone());<\/pre>\n<p>\u4e0a\u9762\u7684\u4ee3\u7801\u4e2d\uff0c_fishbone\u867d\u7136\u548cFish\u5bf9\u8c61\u76f8\u5173\u8054\uff0c\u4f46\u662f\u5374\u65e0\u6cd5\u901a\u8fc7Fish\u5bf9\u8c61\u76f4\u63a5\u83b7\u53d6\u3002<\/p>\n<p>\u5982\u679c\u4e0d\u77e5\u9053\u540d\u79f0\uff0c\u4e5f\u65e0\u6cd5\u901a\u8fc7myWm\u904d\u5386\u51fa\u6765\u3002<\/p>\n<p>\u5173\u4e8eWeakMap\u66f4\u8be6\u7ec6\u7684\u8bed\u6cd5\u4ecb\u7ecd\u548c\u793a\u610f\u53ef\u53c2\u8003MDN\u6587\u6863\uff1a<a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/JavaScript\/Reference\/Global_Objects\/WeakMap\" rel=\"noopener\" target=\"_blank\">MDN WeakMap<\/a><\/p>\n<h3>\u56db\u3001\u7ed3\u675f\u8bed<\/h3>\n<p>\u8003\u8003\u5927\u5bb6\uff0c\u6211\u6628\u5929\u9493\u7684\u4e0b\u97623\u79cd\u9c7c\uff0c\u54ea\u79cd\u9c7c\u6709\u808c\u95f4\u523a\uff0c\u54ea\u51e0\u79cd\u9c7c\u6ca1\u6709\u808c\u95f4\u523a\uff1f<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202108\/myfish-s.jpg\" width=\"240\" height=\"320\" alt=\"\u9493\u8d27\" class=\"alignnone size-medium\" \/><\/p>\n<p>\u597d\uff0c\u672c\u6587\u5185\u5bb9\u5c31\u4e0a\u9762\u8fd9\u4e9b\u3002<\/p>\n<p>\u5982\u679c\u6587\u4e2d\u6709\u8868\u8ff0\u4e0d\u51c6\u786e\u7684\u5730\u65b9\uff0c\u6216\u8005\u6709\u6240\u9057\u6f0f\uff0c\u6b22\u8fce\u6307\u6b63\u3002<\/p>\n<p>\u5982\u679c\u60a8\u89c9\u5f97\u6587\u7ae0\u4e0d\u9519\uff0c\u4e5f\u6b22\u8fce\u5206\u4eab\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"\/\/image.zhangxinxu.com\/image\/emtion\/emoji\/2764.svg\" width=\"20\" height=\"20\" align=\"absmiddle\"><\/p>\n<p>\u672c\u6587\u4e3a\u539f\u521b\u6587\u7ae0\uff0c\u6b22\u8fce\u5206\u4eab\uff0c\u52ff\u5168\u6587\u8f6c\u8f7d\uff0c\u5982\u679c\u5b9e\u5728\u559c\u6b22\uff0c\u53ef\u6536\u85cf\uff0c\u6c38\u4e0d\u8fc7\u671f\uff0c\u4e14\u4f1a\u53ca\u65f6\u66f4\u65b0\u77e5\u8bc6\u70b9\u53ca\u4fee\u6b63\u9519\u8bef\uff0c\u9605\u8bfb\u4f53\u9a8c\u4e5f\u66f4\u597d\u3002<br \/>\n\u672c\u6587\u5730\u5740\uff1a<a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/?p=10064\">https:\/\/www.zhangxinxu.com\/wordpress\/?p=10064<\/a><\/p>\n<p>\uff08\u672c\u7bc7\u5b8c\uff09<\/p>\n","protected":false},"excerpt":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202108\/weakmap-cover.png\" width=\"160\" height=\"113\" alt=\"\u7ea2\u6885\u8461\u8404\u5360\u4f4d\u56fe\" class=\"alignright size-medium\" loading=\"lazy\" \/><\/p>\n<p>\u672c\u6587\u6df1\u5165\u4ecb\u7ecd\u6211\u5bf9ES6\u4e2dWeakMap\u5bf9\u8c61\u7684\u4e00\u4e9b\u7406\u89e3\uff0c\u4ee5\u53ca\u5728\u5185\u5b58\u6027\u80fd\u8fd9\u5757\u7684\u4f5c\u7528\uff0c\u5e0c\u671b\u53ef\u4ee5\u5bf9\u5927\u5bb6\u7684\u5b66\u4e60\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1284],"tags":[904,800,1775],"_links":{"self":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/10064"}],"collection":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/comments?post=10064"}],"version-history":[{"count":0,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/10064\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/media?parent=10064"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/categories?post=10064"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/tags?post=10064"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}