当想要获取一个文件夹下的多个模块/文件
const req = require.context('./modules', false, /\.js$/)
const requireAll = requireContext => requireContext.keys().map(requireContext)
const res = requireAll(req).map(v => v.default)
const req = require.context('./modules', false, /\.js$/)
const requireAll = requireContext => requireContext.keys().map(requireContext)
const res = requireAll(req).map(v => v.default)