Getting Started with Create React App
This project was bootstrapped with Create React App.
Available Scripts
In the project directory, you can run:
yarn start
Runs the app in the development mode.
Open http://localhost:3000 to view it in the browser.
The page will reload if you make edits.
You will also see any lint errors in the console.
yarn test
Launches the test runner in the interactive watch mode.
See the section about running tests for more information.
yarn build
Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.
The build is minified and the filenames include the hashes.
Your app is ready to be deployed!
See the section about deployment for more information.
yarn eject
Note: this is a one-way operation. Once you eject, you can’t go back!
If you aren’t satisfied with the build tool and configuration choices, you can eject at any time. This command will remove the single build dependency from your project.
Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except eject will still work, but they will point to the copied scripts so you can tweak them. At this point you’re on your own.
You don’t have to ever use eject. The curated feature set is suitable for small and middle deployments, and you shouldn’t feel obligated to use this feature. However we understand that this tool wouldn’t be useful if you couldn’t customize it when you are ready for it.
Learn More
You can learn more in the Create React App documentation.
To learn React, check out the React documentation.
##按需加载(cnmp--加快安装) 1.拉取react的配置文件 npm run eject
//eslint-disable-line 实现对eslint该报错的屏蔽
2.classname动态绑定： npm install classnames 使用：
标题
//基础用法 classnames('bold','center') // => 'bold center' classnames('bold',{'center':true}) // => 'bold center' classnames('bold',{'center':false}) // => 'bold'
//各种各样属性结合 classnames('bold',{'center':true,'break':false},{'color':true}) // => 'bold center color'
// 一些不存在/空的属性会自动忽略 classNames(null, false, 'bold', undefined, 0, 1, { baz: null }, ''); // => 'bold 1'
//数组会遍历输出 let classnamesArr = [{'center':true,'break':false},'title']; classnames('bold',classnamesArr); // => 'bold center title'
//字符串模板方式
let fontStyle = 'weight';
classnames(font-${fontStyle}); // => 'font-weight'
classnames({[font-${fontStyle}]:true}); // => 'font-weight'
3.生命周期 componentWillMount 组件render之前 componentDidMount 组件挂载完成以后，也就是 DOM 元素已经插入页面后调用。 componentWillUnmount 组件对应的 DOM 元素从页面中删除之前调用。 shouldComponentUpdate(nextProps, nextState){ return true;} 你可以通过这个方法控制组件是否重新渲染。如果返回 false 组件就不会重新渲染。这个生命周期在 React.js 性能优化上非常有用。默认true componentWillReceiveProps(nextProps)：组件从父组件接收到新的 props 之前调用 componentWillUpdate(nextProps, nextState)：组件开始重新渲染之前调用。 componentDidUpdate(prevProps, prevState)：组件重新渲染并且把更改变更到真实的 DOM 以后调用。
3./*数据刷新 **React.Component PureComponent:浅层数据校验 或者在shouldComponentUpdate 判断处理 */
- context
5.错误边界componentDidCatch
<ErrorBoundary render={(error,errorInfo)=>
{加载错误}
}> <子元素>