我使用的是angular 5.0.3,我想用一堆查询参数启动我的应用程序,比如/app?param1=hallo&param2=123。如何在Angular 2中从url中获取查询参数?对我没用。

有什么想法如何获得查询参数工作?

private getQueryParameter(key: string): string {
  const parameters = new URLSearchParams(window.location.search);
  return parameters.get(key);
}

这个私有函数帮助我获取参数,但我认为在新的Angular环境中这不是正确的方式。

(更新:) 我的主应用程序是这样的

@Component({...})
export class AppComponent implements OnInit {

  constructor(private route: ActivatedRoute) {}

  ngOnInit(): void {
    // would like to get query parameters here...
    // this.route...
  }
}

当前回答

父组件从ActivatedRoute获取空参数

对我有用:

import {Component, OnDestroy, OnInit} from '@angular/core';
import { Router, ActivatedRoute, Params, RoutesRecognized } from '@angular/router';

@Component({
  selector: 'app-navigation-bar',
  templateUrl: './navigation-bar.component.html',
  styleUrls: ['./navigation-bar.component.scss']
})
export class NavigationBarComponent implements OnInit, OnDestroy {
  private sub: any;
  constructor(private route: ActivatedRoute, private router: Router) {}

  ngOnInit() {
    this.sub = this.router.events.subscribe(val => {
      if (val instanceof RoutesRecognized) {
        console.log(val.state.root.firstChild.params);
      }
    });
  }

  ngOnDestroy() {
    this.sub.unsubscribe();
  }

}

其他回答

简单的解决方案

 // in routing file
       {
            path: 'checkout/:cartId/:addressId',
            loadChildren: () => import('./pages/checkout/checkout.module').then(m => m.CheckoutPageModule)
          },

    // in Component file

            import { Router, ActivatedRoute } from '@angular/router';

                 constructor(
                      private _Router: ActivatedRoute
                  ) { }

                  ngOnInit() {
                    this.cartId = this._Router.snapshot.params.cartId;
                    this.addressId = this._Router.snapshot.params.addressId;
                    console.log(this.addressId, "addressId")
                    console.log(this.cartId, "cartId")
                  }
import { ParamMap, Router, ActivatedRoute } from '@angular/router';

constructor(private route: ActivatedRoute) {}

ngOnInit() {
    console.log(this.route.snapshot.queryParamMap);
}

更新

import { Router, RouterStateSnapshot } from '@angular/router';

export class LoginComponent {
    constructor(private router: Router) {
        const snapshot: RouterStateSnapshot = router.routerState.snapshot;
        console.log(snapshot);  // <-- hope it helps
    }
}

你也可以使用HttpParams,比如:

  getParamValueQueryString( paramName ) {
    const url = window.location.href;
    let paramValue;
    if (url.includes('?')) {
      const httpParams = new HttpParams({ fromString: url.split('?')[1] });
      paramValue = httpParams.get(paramName);
    }
    return paramValue;
  }

最好的解决方案是使用ActivatedRoute:

    constructor(private route: ActivatedRoute) {}
    
    ngOnInit(): void {
        this.route.queryParams.subscribe((params) => {
         console.log(params);
         const queryparams = params['queryName'];
        });
    }

如果你没有使用Angular的router try, querystring。安装它

npm install --save querystring

对你的项目。在您的组件中执行如下操作

import * as qs from 'querystring';
...
ngOnInit() {
   const params = qs.parse(window.location.search.substring(1));
   ...
}

子字符串(1)是必要的,因为如果你有这样的'/mypage?Foo =bar'则键名为? Foo