如何解决 Angular 模块导入问题?

How can I solve Angular module import problem?

有效

import { MatButtonModule } from '@angular/material/button'
import { MatMenuModule } from '@angular/material/menu'

不工作

import { MatButtonModule,MatMenuModule } from '@angular/material' 

为什么会这样?

Angular 的第 9 版不再支持它。

Components can no longer be imported through "@angular/material". Use the individual secondary entry-points, such as @angular/material/button.

来源: git issue and changelog