角度4如何在分解器中返回多个观察值

我找到了一个解决这个问题的方法,也许会对某人有所帮助,所以基本上我使用了 forkJoin 组合多个观测值并解析所有观测值。

resolve(route: ActivatedRouteSnapshot): Observable<any> {
        return forkJoin([
                this._elementsService.getElementTypes(),
                this._elementsService.getDepartments()
                .catch(error => {

                    /* if(error.status === 404) {
                        this.router.navigate(['subscription-create']);
                    } */

                    return Observable.throw(error);
                })
        ]).map(result => {
            return {
                types: result[0],
                departments: result[1]
            };
        });
    };

现在它工作正常,正如预期的那样。

您可以使用 withLatestFrom .

下面是Stackblitz中的一个有效演示: https://stackblitz.com/edit/angular-xfd5xx

解决方案如下。

在解析器中,使用 withLatestFrom最晚从 要结合您的观察结果:

import { Injectable } from '@angular/core';
import { Resolve, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router';
import { Library } from '../models/library.model';
import { LibraryBook } from '../models/library-book.model';
import { LibraryService } from '../services/library.service';
import { Observable } from 'rxjs';
import { withLatestFrom } from 'rxjs/operators';

@Injectable()
export class LibraryDisplayResolver implements Resolve<[Library, LibraryBook[]]> {

  constructor(
    private _libraryService: LibraryService,
  ) { }

  resolve (route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<[Library, LibraryBook[]]> {
    const libraryId = route.params['id'];
    return this._libraryService.getLibrary(libraryId).pipe(
      withLatestFrom(
        this._libraryService.getBooksFromLibrary(libraryId)
      )
    );
  }
}

确保在路由中使用适当的标识符设置了解析器:

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { LibraryDisplayComponent } from './library-display.component';
import { LibraryDisplayResolver } from '../resolvers/library-display.resolver';

const routes: Routes = [
  {
    path: ':id',
    component: LibraryDisplayComponent,
    resolve: {
      libraryResolverData: LibraryDisplayResolver
    }
  },
  {
    path: '',
    redirectTo: '1',
    pathMatch: 'full'
  },
];

@NgModule({
  imports: [RouterModule.forChild(routes)],
  exports: [RouterModule]
})
export class LibraryDisplayRoutingModule { }

在接收组件中,您可以访问两个观察对象的快照,如下所示:

import { Component, OnInit } from '@angular/core';
import { LibraryBook } from '../models/library-book.model';
import { Library } from '../models/library.model';
import { ActivatedRoute } from '@angular/router';

@Component({
  // tslint:disable-next-line:component-selector
  selector: 'library-display',
  templateUrl: './library-display.component.html',
  styleUrls: ['./library-display.component.scss']
})
export class LibraryDisplayComponent implements OnInit {

  library: Library;
  libraryBooks: LibraryBook[];

  constructor(
    private route: ActivatedRoute
  ) { }

  ngOnInit() {
    this.library = this.route.snapshot.data['libraryResolverData'][0];
    this.libraryBooks = this.route.snapshot.data['libraryResolverData'][1];
  }
}

我也有类似的情况,但我的处理方式略有不同。

在您的情况下,我的理解是您希望获得查询参数,然后根据响应调用更多的服务。

我这样做的方式是让一个组件包裹其他组件,并传递它们所需的对象。我通过route paramMap订阅它们,然后将所有其他调用打包到a.Observalbe中。分叉连接

在我的包装器组件中,我执行以下操作:

ngOnInit() {

    this.route.params.subscribe((params) => {
        if (params.hasOwnProperty('id') && params['id'] != '') {
            const slug = params['slug'];
            Observable.forkJoin([
                this.myService.getData(id),
                this.myService.getOtherData(id),
            ]).subscribe(
                ([data, otherData]) => {
                    this.data = data;
                    this.otherData = otherData;
                },
                error => {
                    console.log('An error occurred:', error);
                },
                () => {
                    this.loading = false;
                }
                );
        }
    });

不完全是你想要的,但我希望它能为你指明正确的方向

我建议你使用可观察的东西,它们会让你的生活变得很轻松。 查看这两篇文章,了解如何使用可观察对象实现这一目标的更多详细信息:

http://www.syntaxsuccess.com/viewarticle/combining-multiple-rxjs-streams-in-angular-2.0

http://blog.danieleghidoli.it/2016/10/22/http-rxjs-observables-angular/

我个人使用 flatMap

祝你好运

  resolve(route: ActivatedRouteSnapshot) {
let id = route.params['id'];

const getUser = new Promise((resolve, reject) => {
  this.customerService.getSingle(id).subscribe((res) => {
    resolve(res);
  }, (err) => {
    console.log('err', err);
  });
});

const getDocument = new Promise((resolve, reject) => {
  this.customerService.getDocument().subscribe((res) => {
    resolve(res);
  });
});

return Promise.all([getUser, getDocument]);

}