问题描述
一开始,我使用了一个服务,它给了我一个字符串,我将它保存在变量中,并使用大括号将它显示在 HTML 上,但是我没有看到值,我已经测试了服务和值来自后端,所以我认为这种情况是由生命周期造成的。我尝试了 ngOnInit
和 ngAfterViewInit
,但我无法获得该值。
elCodigoInterno: string;
ngOnInit() {
this.iniciarFormulario();
this.dataService.getCodigoInterno().subscribe(
//result => this.colaborador.codigoInterno = result,result => this.elCodigoInterno = result,error => console.log('error ',error)
);
}
ngAfterViewInit(){
this.dataService.getCodigoInterno().subscribe(
//result => this.colaborador.codigoInterno = result,error)
);
}
<label for="codigoInterno">Código Interno </label>
<p>{{elCodigoInterno}} </p>
解决方法
如果在dataService中创建一个public变量,然后在getCodigoInterno方法中赋值给这个变量,就可以得到你想要得到的值。
我可以举个例子
///// 服务
export class LocationService {
public locationlist: Location[] | any;
public location: Location | any;
constructor(private http: HttpClient) { }
public getAllLocation(): Observable<Location[]> {
return this.http.get<ApiResponse>(environment.locationApiUrl,{}).pipe(
map(
(response: ApiResponse) => {
return this.locationlist = response.content;
}
)
);
}
}
///// 组件
public location;
constructor(private locationService: LocationService) { }
ngOnInit(): void {
this.location = this.locationService.locationlist[0].id;
}
public getAlllocations() {
this.locationService.getAllLocation().subscribe(location => {
...
});
}