Question

我使用15.0.1并使用React创建通用应用

我得到的React未在以下组件中定义

import {Component} from "react";

export default class HeroSearchView extends Component{

    render() {

        return (
            <div className='row'>
                hello
            </div>
        );
    }
}

以下代码调用React组件

import React from "react";
import { connect } from 'react-redux'
import Coupon from '../../common/components/Coupon'
import { actions as miscActions } from '../../redux/modules/misc'
import HeroSearchView from './components/HeroSearchView'


const mapStateToProps = (state) => ({
    misc:state.misc
})

export class HomeView extends React.Component{
    render() {

        return (
            <div>
                <HeroSearchView  />
                <Coupon {...this.props} />
            </div>
        );
    }
}

export default connect(mapStateToProps, Object.assign({}, miscActions))(HomeView)

我现在有点挠头，以下信息意味着......

ReferenceError: React is not defined
    at HeroSearchView.render (HeroSearchView.jsx:8:13)
    at [object Object].ReactCompositeComponentMixin._renderValidatedComponentWithoutOwnerOrContext (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactCompositeComponent.js:679:34)
    at [object Object].ReactCompositeComponentMixin._renderValidatedComponent (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactCompositeComponent.js:699:32)
    at [object Object].wrapper [as _renderValidatedComponent] (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactPerf.js:66:21)
    at [object Object].ReactCompositeComponentMixin.performInitialMount (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactCompositeComponent.js:284:30)
    at [object Object].ReactCompositeComponentMixin.mountComponent (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactCompositeComponent.js:237:21)
    at [object Object].wrapper [as mountComponent] (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactPerf.js:66:21)
    at Object.ReactReconciler.mountComponent (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactReconciler.js:39:35)
    at ReactDOMComponent.ReactMultiChild.Mixin.mountChildren (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactMultiChild.js:203:44)
    at ReactDOMComponent.Mixin._createContentMarkup (/Users/roy/development/org/pl-core/node_modules/react/lib/ReactDOMComponent.js:589:32)

[注意] ：如果我从示例代码中删除<HomeSearchView />，则可以正常使用...

任何提示都将受到赞赏......

Answer 1

您需要使用

import React from "react"

和

export default class HeroSearchView extends React.Component

这是因为JSX将您的文件转换为调用React.createElement的实际JS，并且因为您仅从react导入Component，所以无法找到对React的引用

Answer 2

你可以做这样的事情来保持你的代码整洁。

import React, {Component} from "react";

export default class HeroSearchView extends Component {

    render() {

        return (
            <div className='row'>
                hello
            </div>
        );
    }
}

Answer 3

如果您正在使用Rails，那么可能的错误原因是您添加了 //= require react //= require react_ujs //= require components 进入你的app / assets / javascripts / application.js

Answer 4

import React from "react";

export default class HeroSearchView extends React.Component{

    render() {

        return (
            <div className='row'>
                hello
            </div>
        );
    }
}

更改为此，它将起作用。

React没有在简单的React组件中定义（通用）

4 个答案: