目录
一,流程
1，确定目录
2，在目录下运行cmd（shift+鼠标右键+在此处运行命令行），或者cmd下cd切换目录
3，执行create-react-app firsttest 等待运行结束
4，cd firsttest 切换到项目目录下
5，在该目录下可以执行命令
二,命令说明
1，运行的方法，命令行 npm start
Runs the app in the development mode.
Open [http://localhost:3000](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.
2,测试的方法，命令行 npm test
Launches the test runner in the interactive watch mode.
See the section about [running tests](https://facebook.github.io/create-react-app/docs/running-tests) for more information.
3,暂时不知道是什么
npm run 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!
4，高级配置，修改默认配置，会出现几个隐藏的目录
npm run 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.