导航到第一个子级时触发父路由OnInit

const routes: Routes = [
  {
    path: 'parent',
    component: ParentComponent,
    children: [
      {
        path: 'child',
        component: ChildComponent
      }
    ]
  }
];

<router-outlet></router-outlet>

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

@Component({
  selector: 'app-parent',
  templateUrl: './parent.component.html',
  styleUrls: ['./parent.component.css']
})
export class ParentComponent implements OnInit {

  ngOnInit(): void {
    // 在这里编写导航到第一个子级时触发的逻辑代码
    console.log('导航到第一个子级时触发父路由OnInit');
  }

}