我正在通过官方教程学习 Angular 5。我正在阅读服务:服务章节
现在,我在本章中:
看它运行
浏览器刷新后,应用应像以前一样运行,显示 单击英雄名称时的英雄列表和英雄详细信息视图。
我有这个错误:
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.
实际上,我只是按照教程进行操作,并且出现了此错误。
在这里,文件:
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();
}
}
感谢您的帮助
您的财产英雄在 heroes.component.ts
中被错误地声明
你有:
heroes = Hero[];
它应该是:
heroes: Hero[];
一个常见的错误 - 在其他语言中,=
在为实例变量赋值时是有效的,但是由于TypeScript是基于JavaScript的(例如使用JSON对象(,因此您可以使用:
来实现此目的。
尝试将此 heroes = Hero[] 更改为:
heroes: Array<Hero> = [];