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151.07f1a9e9.js

151.07f1a9e9.js 46 KB
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1 
  1. (window.webpackJsonp=window.webpackJsonp||[]).push([[151],{480:function(t,s,a){"use strict";a.r(s);var n=a(3),e=Object(n.a)({},(function(){var t=this,s=t._self._c;return s("ContentSlotsDistributor",{attrs:{"slot-key":t.$parent.slotKey}},[s("h1",{attrs:{id:"_09-状态提升-共享状态"}},[s("a",{staticClass:"header-anchor",attrs:{href:"#_09-状态提升-共享状态"}},[t._v("#")]),t._v(" 09. 状态提升 (共享状态)")]),t._v(" "),s("p",[t._v("通常，"),s("strong",[t._v("多个组件需要反映相同的变化数据，这时我们建议将共享状态提升到最近的共同父组件中去")]),t._v("。")]),t._v(" "),s("p",[t._v("在 React 中，"),s("strong",[t._v("将多个组件中需要共享的 state 向上移动到它们的最近共同父组件中，便可实现共享 state。这就是所谓的“状态提升”")])]),t._v(" "),s("p",[t._v("两个输入框共享数据的例子：")]),t._v(" "),s("div",{staticClass:"language-jsx line-numbers-mode"},[s("pre",{pre:!0,attrs:{class:"language-jsx"}},[s("code",[s("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("const")]),t._v(" scaleNames "),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token 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"),s("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("const")]),t._v(" temperature "),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("this")]),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("state"),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("temperature"),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(";")]),t._v("\n    \n    "),s("span",{pre:!0,attrs:{class:"token comment"}},[t._v("// 根据scale值取得相应的温度数据")]),t._v("\n    "),s("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("const")]),t._v(" celsius "),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" scale "),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v("===")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token string"}},[t._v("'f'")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v("?")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token 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