Angular 2获取Input元素值

在我的HTML代码下面

<div class="messagesholder" *ngFor="let chat of chatval | orderby:'[date]'" >
   <div *ngIf="chat.sender == currentuser || chat.receiver == currentuser">
    <div  *ngIf="chat.date" style="text-align: center;" >
           <p style="font-size:9px;" id="amount" #amount>{{chat.date | amDateFormat:'LL'}}</p>
           <input #myname [ngModel]="range" (ngModelChange)="saverange($event)"/>
         <input #myname type="text" value={{chat.date}}>
    </div>
   </div>
   <div class="message" *ngIf="chat.sender == currentuser || chat.receiver == currentuser" [ngClass]="{'me': currentuser == chat.sender}">
          <div class='image' *ngIf="chat.path" >
            <img *ngIf="chat.path" [src]="chat.path"/><br>
            <span *ngIf="chat.path_text">{{chat.path_text}}</span>
            <span style="font-size:9px;">{{chat.date | amDateFormat:'hh:mmA'}}</span>
          </div> 
           <div *ngIf="chat.message_text">
           <span>{{chat.message_text}}</span>
           <span style="font-size:9px;">{{chat.date | amDateFormat:'hh:mmA'}}</span>
           </div>
    </div>

在我的ts文件下面

import { Component,Inject,ViewChild,ElementRef,AfterViewInit} from '@angular/core';

export class ChatPage implements AfterViewInit {
  @ViewChild('myname') input:ElementRef; 
  constructor(public modalCtrl: ModalController,public navCtrl: NavController) {}
   ngAfterViewInit() {
    console.log(this.input.nativeElement.value);
    }
  }

重复相同的日期值.我希望不重复相同的日期值.

因为我会检查两个变量.

所以我需要chat.date值.因为我绑定了input的值.但是我无法获得input元素的值.

我收到这个错误

无法读取未定义的属性“nativeElement”

如何解决这个问题.或任何其他方式来找到slutions.

谢谢