Angular 2 - 找不到模块 : Error: Can't resolve '@angular/material'

Question

我按照此处描述的每个步骤进行操作:https://material.angular.io/guide/getting-started

我得到的错误

ERROR in ./src/app/app.module.ts
Module not found: Error: Can't resolve '@angular/material' in '/Users/isabelle/my-project/src/app'
@ ./src/app/app.module.ts 14:0-51
@ ./src/main.ts
@ multi webpack-dev-server/client?http://localhost:4200/ ./src/main.ts

我做了什么

npm install -g @angular/cli
ng new my-project
npm install --save @angular/material

在 src/app/app.module.ts

import { MaterialModule } from '@angular/material';
    
    // other imports 
@NgModule({
    imports: [MaterialModule],
    ...
})   
export class PizzaPartyAppModule { }

Answer 1

我再次执行该命令，一切顺利

npm install --save @angular/material