@Output() destroyCheck:EventEmitter<string>=new EventEmitter<string>();

ngOnDestroy(){

          this.destroyCheck.emit('destroyed');

}

在您的父组件处理这种方式.

<div>
     <child-comp (destroyCheck)="someMethod($event)"> </child-comp>
</div>

您的方法应该被处理为

someMethod(something){
  console.log(something);
}