{"id":31466,"date":"2024-11-25T13:07:05","date_gmt":"2024-11-25T05:07:05","guid":{"rendered":"https:\/\/fwq.ai\/blog\/31466\/"},"modified":"2024-11-25T13:07:05","modified_gmt":"2024-11-25T05:07:05","slug":"event-emitter%e7%9a%84%e7%9b%91%e5%90%ac%e4%ba%8b%e4%bb%b6","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/31466\/","title":{"rendered":"Event emitter\u7684\u76d1\u542c\u4e8b\u4ef6"},"content":{"rendered":"

\u8fd9\u6b21\u7ed9\u5927\u5bb6\u5e26\u6765Event emitter\u7684\u76d1\u542c\u4e8b\u4ef6\uff0c\u4f7f\u7528Event emitter\u76d1\u542c\u4e8b\u4ef6\u7684\u6709\u54ea\u4e9b\uff0c\u4e0b\u9762\u5c31\u662f\u5b9e\u6218\u6848\u4f8b\uff0c\u4e00\u8d77\u6765\u770b\u4e00\u4e0b\u3002<\/p>\n

\u4ec0\u4e48\u662f Event Emitter?<\/p>\n

Event emitter \u542c\u8d77\u6765\u53ea\u662f\u89e6\u53d1\u4e00\u4e2a\u4e8b\u4ef6\uff0c\u8fd9\u4e2a\u4e8b\u4ef6\u4efb\u4f55\u4e1c\u897f\u90fd\u80fd\u76d1\u542c\u3002<\/p>\n

\u60f3\u8c61\u4e00\u4e0b\u8fd9\u6837\u7684\u573a\u666f\uff0c\u5728\u4f60\u7684\u5f02\u6b65\u4ee3\u7801\u4e2d\uff0c\u53bb\u201c\u547c\u53eb\u201d\u4e00\u4e9b\u4e8b\u4ef6\u7684\u53d1\u751f\uff0c\u4ee5\u53ca\u8ba9\u4f60\u5176\u4ed6\u90e8\u5206\u90fd\u8981\u542c\u5230\u4f60\u7684\u201c\u547c\u53eb\u201d\u5e76\u4e14\u6ce8\u518c\u4ed6\u4eec\u7684\u60f3\u6cd5\u3002<\/p>\n

\u4e3a\u4e86\u4e0d\u540c\u7684\u76ee\u7684\uff0c\u5bf9\u4e8e Event Emitter \u6a21\u5f0f\u6709\u5927\u91cf\u4e0d\u540c\u7684\u5b9e\u73b0\uff0c\u4f46\u662f\u57fa\u672c\u7684\u60f3\u6cd5\u662f\u4e3a\u4e86\u7ed9\u4e00\u4e2a\u6846\u67b6\u63d0\u4f9b\u4e8b\u4ef6\u7684\u7ba1\u7406\u4ee5\u53ca\u80fd\u591f\u53bb\u8ba2\u9605\u4ed6\u4eec\u3002<\/p>\n

\u5728\u8fd9\u91cc\uff0c\u6211\u4eec\u7684\u76ee\u6807\u521b\u5efa\u5c5e\u4e8e\u6211\u4eec\u81ea\u5df1\u7684 Event Emitter \u53bb\u7406\u89e3\u80cc\u540e\u7684\u79d8\u5bc6\u3002\u6240\u4ee5\uff0c\u8ba9\u6211\u4eec\u770b\u4e00\u4e0b\u4e0b\u9762\u7684\u4ee3\u7801\u662f\u600e\u4e48\u5de5\u4f5c\u7684\u3002<\/p>\n

let input = document.querySelector(\"input[type=\"text\"]\");\r\nlet button = document.querySelector(\"button\");\r\nlet h1 = document.querySelector(\"h1\");\r\nbutton.addEventListener(\"click\", () => {\r\n  emitter.emit(\"event:name-changed\", { name: input.value });\r\n});\r\nlet emitter = new EventEmitter();\r\nemitter.subscribe(\"event:name-changed\", data => {\r\n  h1.innerHTML = `Your name is: ${data.name}`;\r\n});<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8ba9\u6211\u4eec\u5f00\u59cb\u3002<\/p>\n
class EventEmitter {\r\n  constructor() {\r\n    this.events = {};\r\n  }\r\n}<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6211\u4eec\u5148\u521b\u5efa\u4e00\u4e2a EventEmiiter \u7c7b\u4ee5\u53ca\u521d\u59cb\u5316 events \u7a7a\u5bf9\u8c61\u5c5e\u6027\u3002\u8fd9\u4e2a events \u5c5e\u6027\u7684\u76ee\u7684\u662f\u4e3a\u4e86\u5b58\u50a8\u6211\u4eec\u7684\u4e8b\u4ef6\u96c6\u5408\uff0c\u8fd9\u4e2a events \u5bf9\u8c61\u4f7f\u7528\u4e8b\u4ef6\u540d\u5f53\u505a key\uff0c\u7528\u8ba2\u9605\u8005\u96c6\u5408\u5f53\u505a value\u3002\uff08\u53ef\u4ee5\u628a\u6bcf\u4e2a\u8ba2\u9605\u8005\u770b\u4f5c\u662f\u4e00\u4e2a\u51fd\u6570\uff09\u3002<\/p>\n
\u8ba2\u9605\u51fd\u6570<\/h2>\n
subscribe(eventName, fn) {\r\n  if (!this.events[eventName]) {\r\n    this.events[eventName] = [];\r\n  }\r\n  this.events[eventName].push(fn);\r\n}<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8fd9\u4e2a\u8ba2\u9605\u51fd\u6570\u83b7\u53d6\u4e8b\u4ef6\u540d\u79f0\uff0c\u5728\u6211\u4eec\u4e4b\u524d\u7684\u4f8b\u5b50\u4e2d\uff0c\u5b83\u662f “event:name-changed” \u4ee5\u53ca\u4f20\u5165\u4e00\u4e2a\u56de\u8c03\uff0c\u5f53\u6709\u4eba\u8c03\u7528 emit\uff08\u6216\u5c16\u53eb\uff09\u4e8b\u4ef6\u7684\u65f6\u5019\u8c03\u7528\u56de\u8c03\u3002<\/p>\n
\u5728  \u51fd\u6570\u7684\u4f18\u70b9\u4e4b\u4e00\u662f\u51fd\u6570\u662f\u7b2c\u4e00\u5bf9\u8c61\uff0c\u6240\u4ee5\u6211\u4eec\u80fd\u50cf\u4e4b\u524d\u6211\u4eec\u7684\u8ba2\u9605\u65b9\u6cd5\u4e00\u6837\uff0c\u901a\u8fc7\u51fd\u6570\u4f5c\u4e3a\u53e6\u4e00\u4e2a\u3002<\/p>\n
\u5982\u679c\u672a\u6ce8\u518c\u8fd9\u4e2a\u4e8b\u4ef6\uff0c\u6211\u4eec\u9700\u8981\u5728\u7b2c\u4e00\u6b21\u4e3a\u5b83\u8bbe\u7f6e\u4e00\u4e2a\u521d\u59cb\u503c\uff0c\u4e8b\u4ef6\u540d\u79f0\u4f5c\u4e3a key \u4ee5\u53ca\u521d\u59cb\u5316\u4e00\u4e2a\u7a7a\u6570\u7ec4\u8d4b\u503c\u7ed9\u5b83\uff0c\u7136\u540e\u6211\u4eec\u5c06\u51fd\u6570\u653e\u5165\u8fd9\u4e2a\u6570\u7ec4\uff0c\u4ee5\u4fbf\u6211\u4eec\u60f3\u901a\u8fc7 emit \u53bb\u8c03\u7528\u8fd9\u4e2a\u4e8b\u4ef6\u3002<\/p>\n
\u8c03\u7528\u51fd\u6570<\/h2>\n
emit(eventName, data) {\r\n  const event = this.events[eventName];\r\n  if (event) {\r\n    event.forEach(fn => {\r\n      fn.call(null, data);\r\n    });\r\n  }\r\n}<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8fd9\u4e2a\u8c03\u7528\u51fd\u6570\u63a5\u53d7\u4e8b\u4ef6\u540d\uff0c\u8fd9\u4e2a\u4e8b\u4ef6\u540d\u662f\u6211\u4eec\u60f3\u201c\u547c\u53eb\u201d\u7684\u540d\u79f0\uff0c\u4ee5\u53ca\u6211\u4eec\u60f3\u4f20\u9012\u7ed9\u8fd9\u4e2a\u4e8b\u4ef6\u7684\u6570\u636e\u3002\u5982\u679c\u5728\u6211\u4eec\u7684 events \u4e2d\u5b58\u5728\u8fd9\u4e2a\u4e8b\u4ef6\uff0c\u6211\u4eec\u5c06\u5e26\u4e0a\u6570\u636e\u5faa\u73af\u8c03\u7528\u6240\u6709\u8ba2\u9605\u7684\u65b9\u6cd5\u3002<\/p>\n
\u4f7f\u7528\u4e0a\u9762\u7684\u4ee3\u7801\u80fd\u505a\u6211\u4eec\u6240\u8bf4\u7684\u5168\u90e8\u7684\u4e8b\u60c5\u3002\u4f46\u6211\u4eec\u4ecd\u7136\u6709\u4e00\u4e2a\u95ee\u9898\u3002\u5f53\u6211\u4eec\u4e0d\u518d\u9700\u8981\u5b83\u4eec\u7684\u65f6\u5019\uff0c\u6211\u4eec\u9700\u8981\u4e00\u79cd\u65b9\u6cd5\u6765\u53d6\u6d88\u6ce8\u518c\u8fd9\u4e9b\u8ba2\u9605\uff0c\u56e0\u4e3a\u5982\u679c\u4f60\u4e0d\u8fd9\u6837\u505a\uff0c\u5c06\u9020\u6210\u5185\u5b58\u6cc4\u6f0f\u3002<\/p>\n
\u8ba9\u6211\u4eec\u6765\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u901a\u8fc7\u5728\u8ba2\u9605\u51fd\u6570\u4e2d\u8fd4\u56de\u4e00\u4e2a\u53d6\u6d88\u6ce8\u518c\u7684\u65b9\u6cd5\u3002<\/p>\n
subscribe(eventName, fn) {\r\n  if (!this.events[eventName]) {\r\n    this.events[eventName] = [];\r\n  }\r\n  this.events[eventName].push(fn);\r\n  return () => {\r\n    this.events[eventName] = this.events[eventName].filter(eventFn => fn !== eventFn);\r\n  }\r\n}<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u56e0\u4e3a JavaScript \u51fd\u6570\u662f\u7b2c\u4e00\u5bf9\u8c61\uff0c\u4f60\u80fd\u5728\u4e00\u4e2a\u51fd\u6570\u4e2d\u8fd4\u56de\u4e00\u4e2a\u51fd\u6570\u3002\u56e0\u6b64\u73b0\u5728\u6211\u4eec\u80fd\u8c03\u7528\u8fd9\u4e2a\u53d6\u6d88\u6ce8\u518c\u51fd\u6570\uff0c\u5982\u4e0b\uff1a<\/p>\n
let unsubscribe = emitter.subscribe(\"event:name-changed\", data => console.log(data));\r\nunsubscribe();<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u5f53\u6211\u4eec\u8c03\u7528\u53d6\u6d88\u6ce8\u518c\u51fd\u6570\u7684\u65f6\u5019\uff0c\u6211\u4eec\u5220\u9664\u7684\u529f\u80fd\u4f9d\u8d56\u4e8e\u5bf9\u8ba2\u9605\u51fd\u6570\u96c6\u5408\u7684\u7b5b\u9009\u65b9\u6cd5\uff08Array filter\uff09\u3002<\/p>\n
\u548c\u5185\u5b58\u6cc4\u9732\u8bf4\u518d\u89c1\uff01<\/p>\n
\u4ee5\u4e0a\u5c31\u662fEvent emitter\u7684\u76d1\u542c\u4e8b\u4ef6\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":"
\u8fd9\u6b21\u7ed9\u5927\u5bb6\u5e26\u6765Event emitter\u7684\u76d1\u542c\u4e8b\u4ef6\uff0c\u4f7f\u7528Event emitter\u76d1\u542c\u4e8b\u4ef6\u7684\u6709\u54ea\u4e9b\uff0c\u4e0b\u9762\u5c31\u662f\u5b9e\u6218\u6848\u4f8b\uff0c\u4e00\u8d77\u6765\u770b\u4e00\u4e0b\u3002 \u4ec0\u4e48\u662f Event Emitter? Event emitter \u542c\u8d77\u6765\u53ea\u662f\u89e6\u53d1\u4e00\u4e2a\u4e8b\u4ef6\uff0c\u8fd9\u4e2a\u4e8b\u4ef6\u4efb\u4f55\u4e1c\u897f\u90fd\u80fd\u76d1\u542c\u3002 \u60f3\u8c61\u4e00\u4e0b\u8fd9\u6837\u7684\u573a\u666f\uff0c\u5728\u4f60\u7684\u5f02\u6b65\u4ee3\u7801\u4e2d\uff0c\u53bb\u201c\u547c\u53eb\u201d\u4e00\u4e9b\u4e8b\u4ef6\u7684\u53d1\u751f\uff0c\u4ee5\u53ca\u8ba9\u4f60\u5176\u4ed6\u90e8\u5206\u90fd\u8981\u542c\u5230\u4f60\u7684\u201c\u547c\u53eb\u201d\u5e76\u4e14\u6ce8\u518c\u4ed6\u4eec\u7684\u60f3\u6cd5\u3002 \u4e3a\u4e86\u4e0d\u540c\u7684\u76ee\u7684\uff0c\u5bf9\u4e8e Event Emitter \u6a21\u5f0f\u6709\u5927\u91cf\u4e0d\u540c\u7684\u5b9e\u73b0\uff0c\u4f46\u662f\u57fa\u672c\u7684\u60f3\u6cd5\u662f\u4e3a\u4e86\u7ed9\u4e00\u4e2a\u6846\u67b6\u63d0\u4f9b\u4e8b\u4ef6\u7684\u7ba1\u7406\u4ee5\u53ca\u80fd\u591f\u53bb\u8ba2\u9605\u4ed6\u4eec\u3002 \u5728\u8fd9\u91cc\uff0c\u6211\u4eec\u7684\u76ee\u6807\u521b\u5efa\u5c5e\u4e8e\u6211\u4eec\u81ea\u5df1\u7684 Event Emitter \u53bb\u7406\u89e3\u80cc\u540e\u7684\u79d8\u5bc6\u3002\u6240\u4ee5\uff0c\u8ba9\u6211\u4eec\u770b\u4e00\u4e0b\u4e0b\u9762\u7684\u4ee3\u7801\u662f\u600e\u4e48\u5de5\u4f5c\u7684\u3002 let input = document.querySelector(“input[type=”text”]”); let button = document.querySelector(“button”); let h1 = document.querySelector(“h1”); button.addEventListener(“click”, () => { emitter.emit(“event:name-changed”, { name: input.value }); }); let emitter = new EventEmitter(); emitter.subscribe(“event:name-changed”, data => { h1.innerHTML = `Your name is: ${data.name}`; […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19],"tags":[],"class_list":["post-31466","post","type-post","status-publish","format-standard","hentry","category-19"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/31466","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=31466"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/31466\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=31466"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=31466"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=31466"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}