{"id":532,"date":"2026-06-26T12:22:48","date_gmt":"2026-06-26T04:22:48","guid":{"rendered":"https:\/\/mitongxue.cn\/?p=532"},"modified":"2026-06-26T12:22:48","modified_gmt":"2026-06-26T04:22:48","slug":"react%e6%80%bb%e7%bb%93","status":"publish","type":"post","link":"https:\/\/mitongxue.cn\/index.php\/2026\/06\/26\/react%e6%80%bb%e7%bb%93\/","title":{"rendered":"React\u603b\u7ed3"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">\u2fbc\u9636\u7ec4\u4ef6(HOC)\u662f\u4ec0\u4e48\uff1f\u4f60\u5728\u4e1a\u52a1\u4e2d\u4f7f\u2f64\u8fc7\u89e3\u51b3\u4e86\u4ec0\u4e48\u95ee\u9898\u3002<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">HOC\u672c\u8d28\u4e0a\u662f\u2f00\u4e2a\u51fd\u6570\uff0c\u5b83\u63a5\u6536\u2f00\u4e2a\u7ec4\u4ef6\u4f5c\u4e3a\u53c2\u6570\uff0c\u7136\u540e\u8fd4\u56de\u2f00\u4e2a\u65b0\u7684\u7ec4\u4ef6\u3002\u8fd4\u56de\u7684\u65b0\u7ec4\u4ef6\u5c06\u62e5\u6709\u88ab\u5305\u88f9\u7684\u7ec4\u4ef6\u7684\u6240\u6709props\uff0c\u5e76\u4e14\u53ef\u4ee5\u6dfb\u52a0\u989d\u5916\u7684props\u6216\u72b6\u6001\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">HOC\u53ef\u4ee5\u2f64\u4e8e\u62bd\u8c61\u51fa\u7ec4\u4ef6\u4e4b\u95f4\u7684\u5171\u4eab\u4ee3\u7801\uff0c\u4ee5\u589e\u5f3a\u7ec4\u4ef6\u7684\u590d\u2f64\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002\u4e5f\u53ef\u4ee5\u2f64\u4e8e\u63a7\u5236props\uff0c\u5c01\u88c5\u7ec4\u4ef6\u72b6\u6001\uff0c\u6216\u8005\u901a\u8fc7\u5f15\u2f64\uff08ref\uff09\u6765\u8bbf\u95ee\u7ec4\u4ef6\u5b9e\u4f8b\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"838\" height=\"158\" src=\"https:\/\/mitongxue.cn\/wp-content\/uploads\/2026\/06\/image-68.png\" alt=\"\" class=\"wp-image-533\" srcset=\"https:\/\/mitongxue.cn\/wp-content\/uploads\/2026\/06\/image-68.png 838w, https:\/\/mitongxue.cn\/wp-content\/uploads\/2026\/06\/image-68-300x57.png 300w, https:\/\/mitongxue.cn\/wp-content\/uploads\/2026\/06\/image-68-768x145.png 768w\" sizes=\"auto, (max-width: 838px) 100vw, 838px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u8fd9\u4e2a\u793a\u4f8b\u4e2d\uff0c withExtraProp \u662f\u2f00\u4e2aHOC\uff0c\u5b83\u63a5\u6536\u2f00\u4e2a\u7ec4\u4ef6Component \uff0c\u7136\u540e\u8fd4\u56de\u2f00\u4e2a\u65b0\u7684\u7ec4\u4ef6\uff0c\u65b0\u7684\u7ec4\u4ef6\u4f1a\u5411 Component \u6dfb\u52a0\u2f00\u4e2a\u989d\u5916\u7684prop\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u4e1a\u52a1\u4e2d\u53ef\u80fd\u4f1a\u4f7f\u2f64\u5230HOC\u7684\u4f8b\u2f26\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1. <strong>\u6388\u6743\u548c\u6743\u9650\u7ba1\u7406\uff1a <\/strong>\u4f8b\u5982\uff0c\u4f60\u53ef\u80fd\u6709\u2f00\u4e9b\u7ec4\u4ef6\u53ea\u5141\u8bb8\u8ba4\u8bc1\u8fc7\u7684\u2f64\u6237\u8bbf\u95ee\u3002\u4f60\u53ef\u4ee5\u521b\u5efa\u2f00\u4e2aHOC\uff0c\u5b83\u63a5\u6536\u2f00\u4e2a\u7ec4\u4ef6\u5e76\u8fd4\u56de\u2f00\u4e2a\u65b0\u7684\u7ec4\u4ef6\uff0c\u65b0\u7684\u7ec4\u4ef6\u5728\u6e32\u67d3\u4e4b\u524d\u4f1a\u68c0\u67e5\u2f64\u6237\u662f\u5426\u5df2\u7ecf\u8ba4\u8bc1\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2. <strong>\u6570\u636e\u83b7\u53d6\uff1a <\/strong>\u53e6\u2f00\u4e2a\u5e38\u2ec5\u7684HOC\u2f64\u4f8b\u662f\u2f64\u4e8e\u6570\u636e\u83b7\u53d6\u3002\u4f8b\u5982\uff0c\u4f60\u53ef\u4ee5\u521b\u5efa\u2f00\u4e2aHOC\uff0c\u5b83\u63a5\u6536\u2f00\u4e2a\u7ec4\u4ef6\u5e76\u8fd4\u56de\u2f00\u4e2a\u65b0\u7684\u7ec4\u4ef6\uff0c\u65b0\u7684\u7ec4\u4ef6\u5728\u6302\u8f7d\u65f6\u83b7\u53d6\u6570\u636e\uff0c\u5e76\u5c06\u6570\u636e\u901a\u8fc7props\u4f20\u9012\u7ed9\u88ab\u5305\u88f9\u7684\u7ec4\u4ef6\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">3. <strong>\u9519\u8bef\u5904\u7406\uff1a <\/strong>\u4f60\u53ef\u4ee5\u521b\u5efa\u2f00\u4e2aHOC\uff0c\u5b83\u63a5\u6536\u2f00\u4e2a\u7ec4\u4ef6\u5e76\u8fd4\u56de\u2f00\u4e2a\u65b0\u7684\u7ec4\u4ef6\uff0c\u65b0\u7684\u7ec4\u4ef6\u5305\u88f9\u539f\u7ec4\u4ef6\u7684\u6e32\u67d3\uff0c\u5e76\u5728\u53d1\u2f63\u9519\u8bef\u65f6\u663e\u793a\u9519\u8bef\u4fe1\u606f\u6216\u5176\u4ed6\u5907\u2f64\u5185\u5bb9\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4ec0\u4e48\u65f6\u5019\u5e94\u8be5\u4f7f\u2f64\u7c7b\u7ec4\u4ef6\u2f7d\u4e0d\u662f\u51fd\u6570\u7ec4\u4ef6\uff1fReact\u7ec4\u4ef6\u9519\u8bef\u6355\u83b7\u600e\u4e48\u505a\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u9519\u8bef\u8fb9\u754c\u662fReact\u4e2d\u7684\u2f00\u79cd\u7279\u6027\uff0c\u5b83\u5141\u8bb8\u4f60\u5728\u2f26\u7ec4\u4ef6\u6811\u4e2d\u6355\u83b7JavaScript\u9519\u8bef\uff0c\u5e76\u5728\u53d1\u2f63\u9519\u8bef\u65f6\u663e\u793a\u5907\u2f64\u5185\u5bb9\uff0c\u2f7d\u4e0d\u662f\u8ba9\u6574\u4e2a\u7ec4\u4ef6\u6811\u5d29\u6e83\u3002\u9519\u8bef\u8fb9\u754c\u5728React\u4e2d\u53ea\u80fd\u901a\u8fc7\u7c7b\u7ec4\u4ef6\u6765\u5b9e\u73b0\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class ErrorBoundary extends React.Component {\n  state = { hasError: false, errMsg: \"\" };\n\n  \/\/ \u6355\u83b7\u9519\u8bef\uff0c\u66f4\u65b0state\n  static getDerivedStateFromError(error) {\n    return { hasError: true, errMsg: error.message };\n  }\n\n  \/\/ \u6355\u83b7\u9519\u8bef\u65e5\u5fd7\uff0c\u4e0a\u62a5\u57cb\u70b9\n  componentDidCatch(error, info) {\n    console.error(\"\u7ec4\u4ef6\u6e32\u67d3\u5f02\u5e38\uff1a\", error, info.componentStack);\n    \/\/ \u4e0a\u62a5\u9519\u8bef\u76d1\u63a7\u5e73\u53f0\n    \/\/ reportError(error, info);\n  }\n\n  render() {\n    if (this.state.hasError) {\n      return this.props.fallback || &lt;div>\u9875\u9762\u52a0\u8f7d\u51fa\u9519\uff0c\u8bf7\u5237\u65b0\u91cd\u8bd5&lt;\/div>;\n    }\n    return this.props.children;\n  }\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;ErrorBoundary fallback={&lt;div>\u6e32\u67d3\u5931\u8d25&lt;\/div>}>\n  &lt;PageContent \/>\n&lt;\/ErrorBoundary><\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u6837\uff0c\u5982\u679c MyWidget \u7ec4\u4ef6\u6216\u8005\u5b83\u7684\u2f26\u7ec4\u4ef6\u5728\u6e32\u67d3\u8fc7\u7a0b\u4e2d\u53d1\u2f63\u9519\u8bef\uff0c ErrorBoundary \u5c31\u4f1a\u6355\u83b7\u5230\u8fd9\u4e2a\u9519\u8bef\uff0c\u5e76\u663e\u793a\u5907\u2f64UI\uff0c\u2f7d\u4e0d\u4f1a\u5bfc\u81f4\u6574\u4e2a\u5e94\u2f64\u5d29\u6e83\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">React \u4e2d\u5982\u4f55\u521b\u5efaRefs\uff1f\u521b\u5efaRefs\u7684\u2f45\u5f0f\u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728React\u4e2d\uff0cRefs\u4e3b\u8981\u2f64\u4e8e\u83b7\u53d6\u548c\u64cd\u4f5cDOM\u5143\u7d20\u6216\u8005React\u7ec4\u4ef6\u7684\u5b9e\u4f8b\uff0c\u662f\u2f00\u79cd\u9003\u8131props\u4f20\u9012\u7684\u2f45\u6cd5\u3002React\u4e2d\u521b\u5efaRefs\u7684\u4e3b\u8981\u2f45\u5f0f\u6709\u4e24\u79cd\uff1a React.createRef() \u548c\u56de\u8c03Refs\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1. React.createRef() : \u8fd9\u662fReact 16.3\u7248\u672c\u540e\u63a8\u51fa\u7684\u65b0API\uff0c\u4f7f\u2f64\u8fd9\u79cd\u2f45\u5f0f\u521b\u5efa\u7684Ref\u53ef\u4ee5\u5728\u6574\u4e2a\u7ec4\u4ef6\u7684\u2f63\u547d\u5468\u671f\u4e2d\u4fdd\u6301\u4e0d\u53d8\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class MyComponent extends React.Component {\nconstructor(props) {\nsuper(props);\nthis.myRef = React.createRef();\n }\ncomponentDidMount() {\nconst node = this.myRef.current;\n\/\/ \u4f60\u73b0\u5728\u53ef\u4ee5\u8bbf\u95eeDOM\u8282\u70b9\u6216\u8005\u7ec4\u4ef6\u5b9e\u4f8b\n }\nrender() {\nreturn &lt;div ref={this.myRef} \/>;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">2. \u56de\u8c03Refs: \u9664\u4e86 React.createRef() \u5916\uff0c\u4f60\u8fd8\u53ef\u4ee5\u4f7f\u2f64\u2f00\u4e2a\u51fd\u6570\u4f5c\u4e3aRef\u3002\u8fd9\u4e2a\u51fd\u6570\u5c06\u4f1a\u5728\u7ec4\u4ef6\u6302\u8f7d\u548c\u5378\u8f7d\u65f6\u5206\u522b\u88ab\u8c03\u2f64\uff0c\u5e76\u5c06DOM\u8282\u70b9\u6216\u7ec4\u4ef6\u5b9e\u4f8b\u4f5c\u4e3a\u53c2\u6570\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class MyComponent extends React.Component {\ncomponentDidMount() {\n\/\/ \u4f60\u73b0\u5728\u53ef\u4ee5\u8bbf\u95eeDOM\u8282\u70b9\u6216\u8005\u7ec4\u4ef6\u5b9e\u4f8b\n }\nrender() {\nreturn &lt;div ref={node => (this.myRef = node)} \/>;\n }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u4e24\u79cdRefs\u521b\u5efa\u2f45\u5f0f\u7684\u4e3b\u8981\u533a\u522b\u5728\u4e8e\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">React.createRef() \u521b\u5efa\u7684Ref\u66f4\u7b80\u6d01\uff0cAPI\u66f4\u2f00\u81f4\uff0c\u2f7d\u4e14Ref\u7684\u503c\u5728\u7ec4\u4ef6\u7684\u6574\u4e2a\u2f63\u547d\u5468\u671f\u4e2d\u4fdd\u6301\u4e0d\u53d8\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u56de\u8c03Refs\u66f4\u7075\u6d3b\uff0c\u5b83\u5141\u8bb8\u4f60\u5728\u7ec4\u4ef6\u6302\u8f7d\u548c\u5378\u8f7d\u65f6\u6267\u2f8f\u2f00\u4e9b\u989d\u5916\u7684\u903b\u8f91\u3002\u4f46\u662f\uff0c\u5982\u679c\u56de\u8c03\u51fd\u6570\u662f\u5728 render \u2f45\u6cd5\u4e2d\u5b9a\u4e49\u7684\uff0c\u90a3\u4e48\u6bcf\u6b21 render \u65f6\u90fd\u4f1a\u521b\u5efa\u2f00\u4e2a\u65b0\u7684\u51fd\u6570\u5b9e\u4f8b\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u2f00\u4e9b\u6027\u80fd\u95ee\u9898\u3002\u603b\u7684\u6765\u8bf4\uff0c\u9664\u2fae\u4f60\u6709\u7279\u6b8a\u9700\u6c42\uff0c\u5426\u5219\u5efa\u8bae\u4f7f\u2f64 React.createRef() \u6765\u521b\u5efaRef\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728<strong>\u51fd\u6570\u7ec4\u4ef6<\/strong>\u4e2d\uff0c\u4f60\u53ef\u4ee5\u4f7f\u2f64 React.useRef() \u548c \u56de\u8c03 Refs \u6765\u521b\u5efa Refs\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1. React.useRef() \uff1a\u8fd9\u662f React Hooks API \u7684\u2f00\u90e8\u5206\uff0c\u53ef\u4ee5\u5728\u51fd\u6570\u7ec4\u4ef6\u4e2d\u4f7f\u2f64\u3002\u4f7f\u2f64 useRef \u521b\u5efa\u7684 Ref \u5728\u6574\u4e2a\u7ec4\u4ef6\u7684\u2f63\u547d\u5468\u671f\u4e2d\u4fdd\u6301\u4e0d\u53d8\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import React, { useRef } from 'react';\nfunction MyComponent() {\nconst myRef = useRef(null);\nReact.useEffect(() => {\nconst node = myRef.current;\n\/\/ \u4f60\u73b0\u5728\u53ef\u4ee5\u8bbf\u95ee DOM \u8282\u70b9\u6216\u8005\u7ec4\u4ef6\u5b9e\u4f8b\n }, &#91;]);\nreturn &lt;div ref={myRef} \/>;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">2. \u56de\u8c03 Refs: \u4f60\u4e5f\u53ef\u4ee5\u5728\u51fd\u6570\u7ec4\u4ef6\u4e2d\u4f7f\u2f64\u56de\u8c03 Refs\u3002\u8fd9\u79cd\u2f45\u5f0f\u4e0b\uff0c\u4f60\u4f1a\u63d0\u4f9b\u2f00\u4e2a\u51fd\u6570\uff0c\u8be5\u51fd\u6570\u4f1a\u5728\u7ec4\u4ef6\u6302\u8f7d\u548c\u5378\u8f7d\u65f6\u5206\u522b\u88ab\u8c03\u2f64\uff0c\u5e76\u5c06 DOM \u8282\u70b9\u6216\u7ec4\u4ef6\u5b9e\u4f8b\u4f5c\u4e3a\u53c2\u6570\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import React, { useEffect, useState } from 'react';\nfunction MyComponent() {\nconst &#91;myRef, setMyRef] = useState(null);\nuseEffect(() => {\nif (myRef) {\n\/\/ \u4f60\u73b0\u5728\u53ef\u4ee5\u8bbf\u95ee DOM \u8282\u70b9\u6216\u8005\u7ec4\u4ef6\u5b9e\u4f8b\n }\n }, &#91;myRef]);\nreturn &lt;div ref={node => setMyRef(node)} \/>;\n}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">createContext\u89e3\u51b3\u4e86\u4ec0\u4e48\u95ee\u9898\uff1fReact\u2f57\u7ec4\u4ef6\u5982\u4f55\u4e0e\u2f26\u7ec4\u4ef6\u901a\u4fe1\uff1f\u2f26\u7ec4\u4ef6\u5982\u4f55\u6539\u53d8\u2f57\u7ec4\u4ef6\u7684\u72b6\u6001\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">React\u7684 createContext API\u4e3b\u8981\u89e3\u51b3\u4e86props\u201c\u7a7f\u900f\u201d\u7684\u95ee\u9898\uff0c\u5373\u4f60\u9700\u8981\u628a\u2f00\u4e2aprop\u5c42\u5c42\u4f20\u9012\u7ed9\u6df1\u5c42\u5d4c\u5957\u7684\u2f26\u7ec4\u4ef6\u3002\u8fd9\u5728\u5e94\u2f64\u4e2d\u6709\u2f00\u4e9b\u5168\u5c40\u53ef\u2f64\u7684\u6570\u636e\u65f6\uff08\u5982\u4e3b\u9898\uff0c\u2f64\u6237\u4fe1\u606f\u7b49\uff09\u2fae\u5e38\u6709\u2f64\u3002\u901a\u8fc7\u521b\u5efa\u2f00\u4e2acontext\uff0c\u4f60\u53ef\u4ee5\u8ba9\u7ec4\u4ef6\u76f4\u63a5\u8bbf\u95ee\u8fd9\u4e9b\u6570\u636e\uff0c\u2f46\u9700\u901a\u8fc7props\u5c42\u5c42\u4f20\u9012\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import React, { createContext, useContext } from 'react';\n\/\/ \u521b\u5efa\u2f00\u4e2aContext\u5bf9\u8c61\nconst ThemeContext = createContext('light');\nfunction App() {\n\/\/ \u4f7f\u2f64Provider\u7ec4\u4ef6\u6765\u63d0\u4f9bcontext\u7684\u503c\nreturn (\n&lt;ThemeContext.Provider value=\"dark\">\n&lt;Toolbar \/>\n&lt;\/ThemeContext.Provider>\n );\n}\nfunction Toolbar() {\nreturn &lt;Button \/>;\n}\nfunction Button() {\n\/\/ \u4f7f\u2f64useContext Hook\u6765\u6d88\u8d39context\u7684\u503c\nconst theme = useContext(ThemeContext);\nreturn &lt;button>{theme}&lt;\/button>;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c\u6211\u4eec\u2fb8\u5148\u4f7f\u2f64 createContext \u521b\u5efa\u4e86\u2f00\u4e2a ThemeContext \u3002\u7136\u540e\uff0c\u6211\u4eec\u5728 App \u7ec4\u4ef6\u4e2d\u4f7f\u2f64 ThemeContext.Provider \u6765\u63d0\u4f9bcontext\u7684\u503c\u3002\u6700\u540e\uff0c\u5728 Button \u7ec4\u4ef6\u4e2d\uff0c\u6211\u4eec\u4f7f\u2f64 useContext Hook\u6765\u6d88\u8d39context\u7684\u503c\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">React\u2f57\u7ec4\u4ef6\u5982\u4f55\u4e0e\u2f26\u7ec4\u4ef6\u901a\u4fe1\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u2f57\u7ec4\u4ef6\u901a\u8fc7props\u5411\u2f26\u7ec4\u4ef6\u4f20\u9012\u6570\u636e\u548c\u51fd\u6570\u3002\u2f26\u7ec4\u4ef6\u53ef\u4ee5\u901a\u8fc7props\u83b7\u53d6\u5230\u8fd9\u4e9b\u6570\u636e\u548c\u51fd\u6570\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u2f26\u7ec4\u4ef6\u5982\u4f55\u6539\u53d8\u2f57\u7ec4\u4ef6\u7684\u72b6\u6001\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u2f26\u7ec4\u4ef6\u2f46\u6cd5\u76f4\u63a5\u6539\u53d8\u2f57\u7ec4\u4ef6\u7684\u72b6\u6001\u3002\u4f46\u662f\uff0c\u2f57\u7ec4\u4ef6\u53ef\u4ee5\u901a\u8fc7props\u5411\u2f26\u7ec4\u4ef6\u4f20\u9012\u2f00\u4e2a\u51fd\u6570\uff0c\u2f26\u7ec4\u4ef6\u8c03\u2f64\u8fd9\u4e2a\u51fd\u6570\u5c31\u80fd\u95f4\u63a5\u5730\u6539\u53d8\u2f57\u7ec4\u4ef6\u7684\u72b6\u6001\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import React, { useState } from 'react';\nfunction Parent() {\nconst &#91;count, setCount] = useState(0);\nconst handleIncrement = () => {\nsetCount(prevCount => prevCount + 1);\n };\nreturn (\n&lt;div>\n&lt;p>Count: {count}&lt;\/p>\n&lt;Child onIncrement={handleIncrement} \/>\n&lt;\/div>\n );\n}\nfunction Child({ onIncrement }) {\nreturn &lt;button onClick={onIncrement}>Increment&lt;\/button>;\n}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">memo\u6709\u4ec0\u4e48\u2f64\u9014\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">React \u4e2d\u7684 memo \u662f\u2f00\u4e2a\u2fbc\u9636\u7ec4\u4ef6\uff0c\u5b83\u2f64\u4e8e\u4f18\u5316\u7ec4\u4ef6\u7684\u6e32\u67d3\u6027\u80fd\u3002 memo \u53ef\u4ee5\u5c06\u2f00\u4e2a\u7eaf\u51fd\u6570\u7ec4\u4ef6\uff08\u2f46\u72b6\u6001\u7ec4\u4ef6\uff09\u5305\u88c5\u8d77\u6765\uff0c\u4ee5\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u91cd\u65b0\u6e32\u67d3\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">useMemo\u4e13\u2f64\u7684hooks\uff0c\u7f13\u5b58\u503c\u3002useCallback\u2f00\u822c\u7f13\u5b58\u6211\u4eec\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">React.memo \u7684\u2f64\u9014\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">React.memo \u662f\u2f00\u4e2a\u2fbc\u9636\u7ec4\u4ef6\uff0c\u5b83\u7c7b\u4f3c\u4e8e React.PureComponent \uff0c\u4f46\u53ea\u9002\u2f64\u4e8e\u51fd\u6570\u7ec4\u4ef6\uff0c\u4e0d\u9002\u2f64\u4e8e\u7c7b\u7ec4\u4ef6\u3002 React.memo \u5bf9\u2f00\u4e2a\u7ec4\u4ef6\u8fdb\u2f8f\u5c01\u88c5\uff0c\u4f7f\u5176\u4ec5\u5728props \u6539\u53d8\u65f6\u8fdb\u2f8f\u91cd\u65b0\u6e32\u67d3\uff0c\u2f7d\u4e0d\u662f\u6bcf\u6b21\u2f57\u7ec4\u4ef6\u91cd\u65b0\u6e32\u67d3\u65f6\u90fd\u8fdb\u2f8f\u6e32\u67d3\u3002\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u6e32\u67d3\uff0c\u63d0\u2fbc\u6027\u80fd\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">useMemo \u548c memo \u7684\u533a\u522b\uff1a<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">useMemo \u662f\u2f00\u4e2a Hook\uff0c\u5b83\u2f64\u4e8e\u907f\u514d\u6267\u2f8f\u6602\u8d35\u7684\u8ba1\u7b97\u64cd\u4f5c\u3002\u5f53\u4f9d\u8d56\u9879\u6539\u53d8\u65f6\uff0c useMemo \u5c06\u91cd\u65b0\u8ba1\u7b97\u7f13\u5b58\u7684\u503c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const memoizedValue = useMemo(() => computeExpensiveValue(a, b),\n&#91;a, b]);<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">React.memo \u662f\u2f00\u4e2a\u2fbc\u9636\u7ec4\u4ef6\uff0c\u5b83\u2f64\u4e8e\u907f\u514d\u51fd\u6570\u7ec4\u4ef6\u8fdb\u2f8f\u4e0d\u5fc5\u8981\u7684\u91cd\u65b0\u6e32\u67d3\u3002\u7b80\u5355\u6765\u8bf4\uff0c useMemo \u662f\u2f64\u4e8e\u4f18\u5316\u8ba1\u7b97\u64cd\u4f5c\uff0c\u2f7d React.memo \u662f\u2f64\u4e8e\u4f18\u5316\u6e32\u67d3\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">useCallback \u548c useMemo \u7684\u533a\u522b\uff1a<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">useCallback \u548c useMemo \u90fd\u662f\u2f64\u4e8e\u4f18\u5316\u7684 Hook\uff0c\u4f46\u5b83\u4eec\u2f64\u4e8e\u4f18\u5316\u7684\u5bf9\u8c61\u4e0d\u540c\u3002useCallback \u2f64\u4e8e\u8fd4\u56de\u2f00\u4e2a memoized \u7684\u56de\u8c03\u51fd\u6570\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const memoizedCallback = useCallback(() => {\ndoSomething(a, b);\n}, &#91;a, b]);<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">useMemo \u2f64\u4e8e\u8fd4\u56de\u2f00\u4e2a memoized \u7684\u503c\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const memoizedValue = useMemo(() => computeExpensiveValue(a, b),\n&#91;a, b]);<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u4f60\u6709\u2f00\u4e2a\u4f9d\u8d56\u4e8e\u67d0\u4e9b\u503c\u7684\u51fd\u6570\uff0c\u5e76\u4e14\u4f60\u60f3\u9632\u2f4c\u8fd9\u4e2a\u51fd\u6570\u5728\u8fd9\u4e9b\u503c\u672a\u6539\u53d8\u65f6\u88ab\u91cd\u65b0\u521b\u5efa\uff0c\u90a3\u4e48\u4f60\u5e94\u8be5\u4f7f\u2f64 useCallback \u3002\u5982\u679c\u4f60\u6709\u2f00\u4e2a\u4f9d\u8d56\u4e8e\u67d0\u4e9b\u503c\u7684\u6602\u8d35\u8ba1\u7b97\uff0c\u5e76\u4e14\u4f60\u60f3\u9632\u2f4c\u8fd9\u4e2a\u8ba1\u7b97\u5728\u8fd9\u4e9b\u503c\u672a\u6539\u53d8\u65f6\u88ab\u91cd\u65b0\u6267\u2f8f\uff0c\u90a3\u4e48\u4f60\u5e94\u8be5\u4f7f\u2f64useMemo \u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">React\u4e2d\u7684\u72b6\u6001\u7ba1\u7406\u5e93\u4f60\u5982\u4f55\u9009\u62e9\uff1f\u4ec0\u4e48\u662f\u72b6\u6001\u6495\u88c2\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Redux: \u8fd9\u662f\u6700\u5e38\u2ec5\u7684\u72b6\u6001\u7ba1\u7406\u5e93\uff0c\u9002\u2f64\u4e8e\u2f24\u578b\u5e94\u2f64\u548c\u9700\u8981\u8de8\u7ec4\u4ef6\u5171\u4eab\u72b6\u6001\u7684\u60c5\u51b5\u3002Redux \u63d0\u4f9b\u4e86\u2f00\u4e2a\u96c6\u4e2d\u5f0f\u7684\u72b6\u6001\u5b58\u50a8\uff0c\u53ef\u4ee5\u8ba9\u4f60\u5728\u4efb\u4f55\u5730\u2f45\u8bbf\u95ee\u548c\u4fee\u6539\u72b6\u6001\u3002\u5982\u679c\u4f60\u7684\u5e94\u2f64\u72b6\u6001\u903b\u8f91\u2f50\u8f83\u590d\u6742\uff0c\u6216\u8005\u4f60\u9700\u8981\u5728\u5e94\u2f64\u7684\u4e0d\u540c\u90e8\u5206\u5171\u4eab\u2f24\u91cf\u7684\u72b6\u6001<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Context API <strong>\u548c<\/strong> useState\/useReducer Hooks: \u5bf9\u4e8e\u2f00\u4e9b\u2f29\u578b\u5e94\u2f64\u6216\u7ec4\u4ef6\uff0c\u4f60\u53ef\u80fd\u4e0d\u9700\u8981\u2f00\u4e2a\u5b8c\u6574\u7684\u72b6\u6001\u7ba1\u7406\u5e93\u3002React \u7684 Context API \u548cHooks\uff08\u4f8b\u5982 useState \u548c useReducer\uff09\u53ef\u80fd\u5df2\u7ecf\u2f9c\u591f\u6ee1\u2f9c\u4f60\u7684\u9700\u6c42\u3002\u4f7f\u2f64\u8fd9\u4e9b React \u5185\u7f6e\u7684\u529f\u80fd\uff0c\u4f60\u53ef\u4ee5\u5728\u7ec4\u4ef6\u95f4\u5171\u4eab\u72b6\u6001\uff0c\u2f7d\u2f46\u9700\u6dfb\u52a0\u989d\u5916\u7684\u4f9d\u8d56\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">&#8220;<strong>\u72b6\u6001\u6495\u88c2<\/strong>&#8221; <strong>\u662f\u6307\u5728\u5e76\u53d1\u6e32\u67d3\uff08<\/strong>Concurrent Mode<strong>\uff09\u4e2d\uff0c\u7531\u4e8e\u6e32\u67d3\u7684\u4f18\u5148\u7ea7\u4e0d\u540c\uff0c\u53ef\u80fd\u5bfc\u81f4\u5e94\u2f64\u4e2d\u7684\u4e0d\u540c\u90e8\u5206\u770b\u5230\u7684\u540c\u2f00\u4efd\u5171\u4eab\u72b6\u6001\u4e0d\u2f00\u81f4\u7684\u95ee\u9898\u3002\u8fd9\u662f\u56e0\u4e3a\u5728<\/strong> Concurrent Mode <strong>\u4e0b\uff0c<\/strong>React <strong>\u53ef\u4ee5\u9009\u62e9\u6682\u505c\u3001\u4e2d\u65ad\u6216\u5ef6\u8fdf\u67d0\u4e9b\u66f4\u65b0\uff0c\u4ee5\u4f18\u5148\u5904\u7406\u66f4\u91cd\u8981\u7684\u66f4\u65b0\u3002\u5982\u679c\u4f60\u7684\u72b6\u6001\u66f4\u65b0\u548c\u7ec4\u4ef6\u7684\u6e32\u67d3\u4e0d\u662f\u540c\u6b65\u7684\uff0c\u90a3\u4e48\u5c31\u53ef\u80fd\u51fa\u73b0\u72b6\u6001\u6495\u88c2\u7684\u95ee\u9898\u3002<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">useState \u5230\u5e95\u540c\u6b65\u8fd8\u662f\u5f02\u6b65<\/h2>\n\n\n\n<h2 class=\"wp-block-heading\">1. <strong>\u66f4\u65b0\u72b6\u6001\u7684 setXxx \u51fd\u6570\u672c\u8eab\u662f\u5f02\u6b65\u8c03\u5ea6\uff0c\u4e0d\u662f\u540c\u6b65\u66f4\u65b0 state<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><code>setCount(xxx)<\/code> \u8c03\u7528\u540e\uff0c<strong>\u4e0d\u4f1a\u7acb\u523b\u4fee\u6539\u5f53\u524d\u4f5c\u7528\u57df\u91cc\u7684 state \u503c<\/strong>\uff0c\u4f1a\u653e\u5230\u66f4\u65b0\u961f\u5217\u6279\u91cf\u5904\u7406\uff0c\u7b49\u672c\u8f6e\u6e32\u67d3\u51fd\u6570\u6267\u884c\u5b8c\u518d\u7edf\u4e00\u66f4\u65b0\u3001\u91cd\u6e32\u67d3\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const &#91;count, setCount] = useState(0);\n\nconst add = () => {\n  setCount(count + 1);\n  console.log(count); \/\/ \u6253\u5370 0\uff0c\u4e0d\u662f 1\uff01\n};<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u539f\u56e0\uff1a\u6267\u884c <code>setCount<\/code> \u53ea\u662f\u63d0\u4ea4\u66f4\u65b0\u4efb\u52a1\uff0c\u5f53\u524d <code>count<\/code> \u8fd8\u662f\u95ed\u5305\u91cc\u65e7\u503c\uff0c\u6e32\u67d3\u5b8c\u6210\u540e\u624d\u66f4\u65b0\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6279\u91cf\u66f4\u65b0\u673a\u5236\uff08\u8868\u73b0\u51fa \u201c\u5f02\u6b65\u201d \u7684\u6839\u6e90\uff09<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u2460 \u5408\u6210\u4e8b\u4ef6\uff08onClick\/onChange \u7b49 React \u4e8b\u4ef6\uff09\u3001useEffect \u5185\uff1a\u6279\u91cf\u5408\u5e76\u66f4\u65b0<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u591a\u6b21\u8fde\u7eed set \u4f1a\u5408\u5e76\uff0c\u53ea\u89e6\u53d1\u4e00\u6b21\u91cd\u6e32\u67d3<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const addMulti = () => {\n  setCount(count + 1);\n  setCount(count + 1);\n  setCount(count + 1);\n  \/\/ \u6700\u7ec8\u53ea +1\uff0c\u4e0d\u662f +3\n};<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u60f3\u8981\u57fa\u4e8e\u6700\u65b0\u72b6\u6001\u8fde\u7eed\u66f4\u65b0\uff0c\u7528<strong>\u51fd\u6570\u5f0f\u66f4\u65b0<\/strong>\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>setCount(prev => prev + 1);\nsetCount(prev => prev + 1);\nsetCount(prev => prev + 1);<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u2461 \u539f\u751f\u5f02\u6b65\u56de\u8c03\uff08setTimeout\u3001Promise\u3001fetch\u3001\u539f\u751f addEventListener\uff09\uff1aReact 18 \u524d\u540e\u6709\u533a\u522b<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>React 17 \u53ca\u66f4\u65e9<\/strong>\uff1a\u4e0d\u4f1a\u6279\u91cf\uff0c\u6bcf\u6b21 set \u7acb\u523b\u89e6\u53d1\u6e32\u67d3\uff0c\u770b\u8d77\u6765\u50cf\u540c\u6b65<\/li>\n\n\n\n<li><strong>React 18+ \u5e76\u53d1\u6e32\u67d3\u4e0b<\/strong>\uff1a\u7edf\u4e00\u81ea\u52a8\u6279\u91cf\u66f4\u65b0\uff0c\u65e0\u8bba\u540c\u6b65 \/ \u5f02\u6b65\u56de\u8c03\uff0c\u90fd\u4f1a\u5408\u5e76\u66f4\u65b0<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">React18 \u793a\u4f8b\uff08setTimeout \u5185\u591a\u6b21 set \u4e5f\u53ea\u4f1a\u6e32\u67d3\u4e00\u6b21\uff09\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>const addAsync = () => {\n  setTimeout(() => {\n    setCount(p => p + 1);\n    setCount(p => p + 1);\n  }, 0);\n};<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>state \u7684\u8bfb\u53d6\u662f\u540c\u6b65<\/strong> \u51fd\u6570\u6267\u884c\u65f6\uff0c\u5f53\u524d\u95ed\u5305\u7684 state \u503c\u53ef\u4ee5\u7acb\u523b\u8bfb\u53d6\uff0c\u56fa\u5b9a\u4e0d\u53d8\uff1b <\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>setState \u8c03\u5ea6\u66f4\u65b0\u662f\u5f02\u6b65\u4efb\u52a1<\/strong> \u72b6\u6001\u4fee\u6539\u3001DOM \u66f4\u65b0\u6392\u961f\u5ef6\u540e\u6267\u884c\uff0c\u65e0\u6cd5\u7acb\u523b\u62ff\u5230\u65b0 state\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">.\u5982\u4f55\u7acb\u523b\u62ff\u5230\u66f4\u65b0\u540e\u7684 state\uff1f<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u51fd\u6570\u5f0f\u66f4\u65b0\uff1a\u4f9d\u8d56\u4e0a\u4e00\u6b21 prevState\uff0c\u4e0d\u53d7\u95ed\u5305\u65e7\u503c\u5f71\u54cd<\/li>\n\n\n\n<li>\u7528 useEffect \u76d1\u542c state\uff0cstate \u53d8\u5316\u540e\u6267\u884c\u903b\u8f91<\/li>\n\n\n\n<li><\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>useEffect(() =&gt; {\n  \/\/ \u8fd9\u91cc\u662f\u6700\u65b0\u7684count\n  console.log(\"\u66f4\u65b0\u540e\", count);\n}, &#91;count])\n<\/code><\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li>useRef \u5b58\u4e00\u4efd\u5b9e\u65f6\u6570\u636e\uff08\u4e0d\u89e6\u53d1\u6e32\u67d3\uff09<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u2fbc\u9636\u7ec4\u4ef6(HOC)\u662f\u4ec0\u4e48\uff1f\u4f60\u5728\u4e1a\u52a1\u4e2d\u4f7f\u2f64\u8fc7\u89e3\u51b3\u4e86\u4ec0..<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12,11,23],"tags":[],"class_list":["post-532","post","type-post","status-publish","format-standard","hentry","category-react-","category-front","category-23"],"featured_image_urls":{"full":"","thumbnail":"","medium":"","medium_large":"","large":"","1536x1536":"","2048x2048":""},"author_info":{"info":["\u9648 \u67d0\u4eba"]},"category_info":"<a href=\"https:\/\/mitongxue.cn\/index.php\/category\/front\/react-%e5%89%8d%e7%ab%af\/\" rel=\"category tag\">React<\/a> <a href=\"https:\/\/mitongxue.cn\/index.php\/category\/front\/\" rel=\"category tag\">\u524d\u7aef<\/a> <a href=\"https:\/\/mitongxue.cn\/index.php\/category\/front\/%e8%af%95%e9%a2%98\/\" rel=\"category tag\">\u8bd5\u9898<\/a>","tag_info":"\u8bd5\u9898","comment_count":"0","_links":{"self":[{"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/posts\/532","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/comments?post=532"}],"version-history":[{"count":2,"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/posts\/532\/revisions"}],"predecessor-version":[{"id":535,"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/posts\/532\/revisions\/535"}],"wp:attachment":[{"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/media?parent=532"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/categories?post=532"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mitongxue.cn\/index.php\/wp-json\/wp\/v2\/tags?post=532"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}