要在Angular应用程序中使用queryParams查询参数，需要在路由上声明对应的参数名称。示例代码如下：

在路由定义中声明查询参数名称：

const routes: Routes = [
  { path: 'products', component: ProductListComponent },
  { path: 'products/:id', component: ProductDetailComponent },
  { path: 'login', component: LoginComponent },
  { path: '', redirectTo: '/products', pathMatch: 'full' }
];

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

在组件中获取并使用查询参数：

import { Component, OnInit } from '@angular/core';
import { ActivatedRoute } from '@angular/router';

@Component({
  selector: 'app-product-detail',
  templateUrl: './product-detail.component.html',
  styleUrls: ['./product-detail.component.css']
})
export class ProductDetailComponent implements OnInit {
  productId: number;

  constructor(private route: ActivatedRoute) { }

  ngOnInit() {
    this.productId = +this.route.snapshot.queryParamMap.get('id');
  }
}