Module not found: Error: Can't resolve 'react' in 'E:\webpack\webpack-sample-project\app'

在npm run server的时候，报错：

ERROR in ./app/main.js

Module not found: Error: Can't resolve 'react' in 'E:\webpack\webpack-sample-project\app'

 @ ./app/main.js 3:13-29

执行如下：

npm install -g react

npm install react --save

类似这种依赖项(react,react-dom等)报错，哪个报错执行哪个即可