Angular2 / 4/6将自定义管道过滤列表从HTML传递到组件

我目前正在研究搜索栏组件。使用自定义管道，我可以显示项目的下拉列表。我需要将已过滤的项目列表（项| CustomPipe：search_input）从searchbar.component.html传递到searchbar.component.ts，但我不确定如何

searchbar.component.html

<ul *ngIf="(Items | CustomPipe : search_input).length>0" class="list-group dropdown-container">
    <li *ngFor="let item of Items | CustomPipe : search_input; index as i" [class.active]="i == arrowkeyLocation" (mouseover)=changeStyle($event)
        (mouseleave)=changeStyle($event) (click)="showConfirm(item)" class="list-group-item" [innerHTML]="item.model | highlight : search_input"></li>
</ul>

我目前的做法：

<input #filterSize type="hidden" value="{{(Items | CustomPipe : search_input).length}}">
<input #filterContent type="hidden" value="{{(Items | CustomPipe : search_input)}}">

searchbar.component.ts

export class SearchbarComponent implements OnInit {
 arrowkeyLocation: number = 0;
@ViewChild('filterSize') filterSize: any;
@ViewChild('filterContent') filterContent: any;
@Output() onSelect: EventEmitter<number> = new EventEmitter<number>();
constructor() {
}
ngOnInit() { }
changeStyle(event) {

    let content = this.filterContent.nativeElement.value;
    let dropdownSize = this.filterSize.nativeElement.value;

    if (event.type == "keydown") {
        switch (event.keyCode) {
            case 38: // this is the ascii of arrow up
                if (this.arrowkeyLocation == -1) {
                    this.arrowkeyLocation = dropdownSize;
                }
                this.arrowkeyLocation--;
                break;
            case 40: // this is the ascii of arrow down
                if (this.arrowkeyLocation == dropdownSize) {
                    this.arrowkeyLocation = -1;
                }
                this.arrowkeyLocation++;
                break;
            case 13:
                this.onSelect.emit(content[this.arrowkeyLocation]);
                break;
        }
    }
}

但是，我无法正确检索对象列表（内容变量）。它从html作为[object Object]的字符串值传递到组件。任何人都可以建议解决方法吗？