用create-react-app创建的app更改build后的输出目录

1、npm install -g create-react-app                                          安装create-react-app
    create-react-app my-app                                                     生成react程序
2、npm run eject                                                                       单向操作，自行配置reacat
3、修改config目录下的paths.js文件：
        module.exports配置项中的appBuild修改为要编译输出到的目录：

module.exports = {
dotenv: resolveApp('.env'),
//appBuild: resolveApp('build'),
appBuild: 'D:\\IdeaProjects\\exam-root-master\\exam\\src\\main\\webapp\\ui\\',
appPublic: resolveApp('public'),
appHtml: resolveApp('public/index.html'),
appIndexJs: resolveApp('src/index.js'),
appPackageJson: resolveApp('package.json'),
appSrc: resolveApp('src'),
yarnLockFile: resolveApp('yarn.lock'),
testsSetup: resolveApp('src/setupTests.js'),
appNodeModules: resolveApp('node_modules'),
publicUrl: getPublicUrl(resolveApp('package.json')),
servedPath: getServedPath(resolveApp('package.json')),
};