在angular 8上，刷新页面不会显示来自后端api的数据

// data-resolver.service.ts
import { Injectable } from '@angular/core';
import { Resolve, ActivatedRouteSnapshot } from '@angular/router';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';

@Injectable()
export class DataResolverService implements Resolve<any> {
  constructor(private http: HttpClient) {}

  resolve(route: ActivatedRouteSnapshot): Observable<any> {
    // 发送HTTP请求到后端API获取数据
    return this.http.get('your-backend-api-url');
  }
}

// app-routing.module.ts
import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { YourComponent } from './your-component.component';
import { DataResolverService } from './data-resolver.service';

const routes: Routes = [
  {
    path: 'your-path',
    component: YourComponent,
    resolve: {
      data: DataResolverService, // 使用路由守卫服务加载数据
    },
  },
];

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

// your-component.component.ts
import { Component, OnInit } from '@angular/core';
import { ActivatedRoute } from '@angular/router';

@Component({
  selector: 'app-your-component',
  templateUrl: './your-component.component.html',
  styleUrls: ['./your-component.component.css'],
})
export class YourComponent implements OnInit {
  data: any;

  constructor(private route: ActivatedRoute) {}

  ngOnInit(): void {
    // 从路由守卫的resolve中获取数据
    this.data = this.route.snapshot.data['data'];
  }
}