1 line
78 KiB
JavaScript
1 line
78 KiB
JavaScript
(window.webpackJsonp=window.webpackJsonp||[]).push([[152],{534:function(t,s,a){"use strict";a.r(s);var n=a(5),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:"_08-表单"}},[s("a",{staticClass:"header-anchor",attrs:{href:"#_08-表单"}},[t._v("#")]),t._v(" 08. 表单")]),t._v(" "),s("h2",{attrs:{id:"受控组件-双向数据绑定"}},[s("a",{staticClass:"header-anchor",attrs:{href:"#受控组件-双向数据绑定"}},[t._v("#")]),t._v(" 受控组件（双向数据绑定）")]),t._v(" "),s("p",[t._v("在 HTML 中，表单元素（如"),s("code",[t._v("<input>")]),t._v("、 "),s("code",[t._v("<textarea>")]),t._v(" 和 "),s("code",[t._v("<select>")]),t._v("）通常自己维护 state，并根据用户输入进行更新。而在 React 中，可变状态（mutable state）通常保存在组件的 state 属性中，并且只能通过使用 "),s("a",{attrs:{href:"https://zh-hans.reactjs.org/docs/react-component.html#setstate",target:"_blank",rel:"noopener noreferrer"}},[s("code",[t._v("setState()")]),s("OutboundLink")],1),t._v("来更新。")]),t._v(" "),s("p",[t._v("我们可以把两者结合起来，使 React 的 state 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