官网API：https://docs.angularjs.org/api
官网 docs： https://angular.io/docs
对应的中文文档https://angular.cn/docs
buglist
1.cant find module @angular/animations/brower
$ npm install @angular/animations@latest –save
2.”/animations/browser”’ has no exported member ‘?DomAnimationEngine’
BrowserAnimationModule模块的版本问题，@angular/animations 4.1.3没有问题(这里也不是很固定，打开 package.json和其他版本匹配起来就好）
$ npm install @angular/animations@4.1.3 –save
3.Error: No provider for InjectionToken DocumentToken!
4. cant find module @angular/common/http
只需要重新安装@angular/common即可，即：
$ npm install –save @angular/common
5.跨域请求问题：
Cross-origin redirection to ** denied by Cross-Origin Resource Sharing policy: Origin http://localhost:8101 is not allowed by Access-Control-Allow-Origin.
6. Failed to load resource: Preflight response is not successful
