获取路由查询参数

Question

我正在尝试从rc1迁移到rc4,我无法获取查询字符串参数.ActivatedRoute对象始终为空.

hero.component.ts

import {Component, OnInit} from "@angular/core";
import {Control} from "@angular/common";
import {ROUTER_DIRECTIVES, ActivatedRoute} from '@angular/router';

@Component({
    template: '../partials/main.html',
    directives: [ROUTER_DIRECTIVES]
})

export class HeroComponent implements OnInit {

    constructor(private _activatedRoute: activatedRoute) {

    }

    ngOnInit() {
        this._activatedRoute.params.subscribe(params => {
            console.log(params);
        });
    }
}

main.ts

import {bootstrap} from '@angular/platform-browser-dynamic';
import {HTTP_PROVIDERS, RequestOptions, Http} from '@angular/http';
import {AppRouterProviders} from './app.routes';

bootstrap(AppComponent, [
    AppRouterProviders,
    HTTP_PROVIDERS
]);

app.component.ts

import {Component, OnInit} from '@angular/core';
import {HeroComponent} from './hero.component';
import {RouteConfig, Router, ROUTER_DIRECTIVES} from '@angular/router';


@Component({
    selector: 'my-app',
    templateUrl: '../partials/main.html',
    directives: [
        HeroComponent,
        ROUTER_DIRECTIVES
    ]
})

export class AppComponent {
}

谐音/ main.html中

<a class="nav-link" [routerLink]="['/']" [queryParams]="{st: 'new'}">New</a>

app.routes.ts

import {provideRouter, RouterConfig}  from '@angular/router';
import {HeroComponent} from './hero.component';
import {ErrorComponent} from './error.component';

const routes: RouterConfig = [
    {path:'', component: HeroComponent},
    {path:'**', component: ErrorComponent}
];

export const AppRouterProviders = [
    provideRouter(routes)
];

当我点击链接'新'控制台打印出空对象

对象{}

更新

plunker

Answer 1

更新(2.0.0最终版)

(somepath/:someparam/someotherpath)您可以使用_router.queryParams.subscribe(...)以下方式订阅它们:

export class HeroComponent implements OnInit {
  constructor(private _activatedRoute: ActivatedRoute, private _router:Router) {
    _activatedRoute.queryParams.subscribe(
      params => console.log('queryParams', params['st']));

原版的

如果你想要queryParams而不是路由params(somepath/:someparam/someotherpath),你可以使用_router.routerState.queryParams.subscribe(...)以下方式订阅它们:

export class HeroComponent implements OnInit {
  constructor(private _activatedRoute: ActivatedRoute, private _router:Router) {
    _router.routerState.queryParams.subscribe(
      params => console.log('queryParams', params['st']));

Plunker的例子

Answer 2

很长时间以来，我一直在同一个问题上挣扎。答案是棘手的，在文档中指出：

ActivatedRoute：提供给每个路由 组件的服务，其中包含特定于路由的信息，例如路由参数，静态数据，解析数据，全局查询参数和全局片段。在这里提到

绝妙的答案是'route component'，这意味着ActivatedRoute仅适用于被路由的组件。换句话说，只有组件在路由表中描述。

>在此处阅读晦涩难懂的官方文档。它提到“与插座中加载的组件关联的路线”。我们只能猜测什么是出口...

我编写了一些调查代码，以在独立的app.module.ts中研究此问题：

import { Component, NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { RouterModule, Routes, ActivatedRoute } from '@angular/router';

@Component({
  selector: 'comp1',
  template: `<h4>comp1 works</h4>`,
})
export class Comp1 { }

@Component({
  selector: 'comp2',
  template: `<h4>comp2 works</h4>`,
})
export class Comp2 { }

@Component({
  selector: 'fail',
  template: `<div>Wrong URL:{{url | json}}</div> <h4>Failure page works</h4>`,
})
export class Fail {
  private url: any;
  constructor(public activeRoute: ActivatedRoute) {
    this.url = activeRoute.snapshot.url
  };

}

@Component({
  selector: 'app-root',
  template: `<div>Base URL:{{url | json}}</div> <router-outlet></router-outlet>`,
})
export class App {
  private url: any;
  constructor(public activeRoute: ActivatedRoute) {
    this.url = activeRoute.snapshot.url
  };
}

const appRoutes: Routes = [
  { path: '1', component: Comp1 },
  { path: '2', component: Comp2 },
  { path: '**', component: Fail }
];

@NgModule({
  imports: [BrowserModule, RouterModule.forRoot(appRoutes)],
  declarations: [App, Comp2, Comp1, Fail],
  bootstrap: [App]
})
export class AppModule { }

尝试为以下URI运行模块：

• http：//本地主机：4200/2
• http：//本地主机：4200/1
• http：// localhost：4200 / a / b / c

祝您好运，希望代码能说明性。