Angular webpack: Failed to compile

Question

I am learning Angular 5 with the official tutorial. I am reading the chapter Service: Chapter Service

Now, I am here in the chapter:

See it run

After the browser refreshes, the app should run as before, showing a list of heroes and a hero detail view when you click on a hero name.

And I have this error :

    ERROR in ./src/app/heroes/heroes.component.ts
    Module parse failed: Unexpected token (18:34)
    You may need an appropriate loader to handle this file type.
|     function HeroesComponent(heroService) {
|         this.heroService = heroService;
|         this.heroes = hero_1.Hero[];
|     }
|     HeroesComponent.prototype.ngOnInit = function () {
 @ ./src/app/app.module.ts 12:25-61
 @ ./src/main.ts
 @ multi webpack-dev-server/client?http://0.0.0.0:0 ./src/main.ts*

webpack: Failed to compile.
ERROR in src/app/heroes/heroes.component.ts(13,17): error TS1109: Expression expected.

Actually, I just followed the tutorial and I have this error.

Here, the files:

src/app/app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppComponent } from './app.component';
import { HeroesComponent } from './heroes/heroes.component';

import { FormsModule } from '@angular/forms';
import { MagiciansComponent } from './magicians/magicians.component';
import { HeroDetailComponent } from './hero-detail/hero-detail.component';

import { HeroService } from './hero.service';
import { MessageService } from './message.service';

@NgModule({
  declarations: [
    AppComponent,
    HeroesComponent,
    MagiciansComponent,
    HeroDetailComponent
  ],
  imports: [
    BrowserModule,
    FormsModule
  ],
  providers: [HeroService, MessageService],
  bootstrap: [AppComponent]
})
export class AppModule { }

src/app/heroes.component.ts

import { Component, OnInit } from '@angular/core';
import { Hero } from '../hero';
import { HEROES } from '../mock-heroes';
import { HeroService } from '../hero.service';

@Component({
  selector: 'app-heroes',
  templateUrl: './heroes.component.html',
  styleUrls: ['./heroes.component.css']
})
export class HeroesComponent implements OnInit {

        heroes =  Hero[];
        selectedHero: Hero;

        constructor(private heroService: HeroService) {}

        ngOnInit() {
                this.getHeroes();
        }

        onSelect(hero: Hero): void {
                this.selectedHero = hero;
        }

        getHeroes(): void {
                this.heroes = this.heroService.getHeroes();
        }
}

Thanks for your help

Answer 1

Your property heroes was declared incorrectly in heroes.component.ts .

You have:

heroes = Hero[];

It should be:

heroes: Hero[];

A common mistake - in other languages = is valid when assigning a value to an instance variable, however since TypeScript is JavaScript based (eg uses JSON objects) you use the : to achieve this.

Answer 2

尝试将此英雄=英雄[]更改为：

heroes: Array<Hero> = [];