只有这三种事件才会导致Angular视图的更新，都是异步事件。
Events：如 click, change, input, submit 等用户事件
XMLHttpRequests：比如从远端服务获取数据
Timers： 比如 JavaScript 的自有 API setTimeout(), setInterval()
https://angular.io/guide/lifecycle-hooks
完整源代码：export class BankAccount implements OnChanges{
ngOnChanges(changes: SimpleChanges): void {
debugger;
}
// This property is bound using its original name.
@Input()
bankName: string;
// this property value is bound to a different property name
// when this component is instantiated in a template.
@Input('account-id')
id: string;
// this property is not bound, and is not automatically updated by Angular
normalizedBankName: string;
}
@Component({
selector: 'app',
template: `
`
})
export class App implements OnInit, AfterViewInit{
_bankName = 'Jerry';
ngAfterViewInit(): void {
this._bankName = 'Jerry2';
}
get bankName(){
debugger;
return this._bankName;
}
ngOnInit(): void {
debugger;
}
}父组件的bankName，在OnInit和OnAfterViewInit时都会变化，这也会触发子组件的ngOnChange接口：
