@viewChild parent element using angular data acquisition method and subassembly

A parent component obtains subassembly referenced by local variables, and data acquisition method of the active subassembly

1, the use of sub-assemblies to be named # #footer

<app-footer #footer></app-footer>

2, the method of performing direct access to the parent component subassembly of footer

<button (click)='footer.footerRun()'>获取子组件的数据</button>

Second, the method of access to data and active subassembly through ViewChild

1, the use of sub-assemblies to be named # #

<app-footer #footerChild></app-footer>

2, the introduction ViewChild

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

3, ViewChild and just subcomponents associate

@ViewChild('footerChild') footer;

4, sub-assemblies footer calling method

run(){
this.footer.footerRun();
}