Angular 4 Ngx-datatable Filter非工作对象为null但是被访问(即使是if条件)

这是我的代码：

import {Component,OnInit,ViewChild,ViewEncapsulation} from '@angular/core';
import {NavbarservicE} from '../../services/navbar.service';
import {DataservicE} from '../../services/data.service';
import {DatatableComponent} from '@swimlane/ngx-datatable';
import {forEach} from '@angular/router/src/utils/collection';

@Component({
  SELEctor: 'app-student',templateUrl: './student.component.html',styleUrls: ['./student.component.css'],encapsulation: ViewEncapsulation.None
})
export class studentComponent implements OnInit {
  rows: student[];
  @ViewChild('myTable') table: any;

  students: student[];
  temp = [];

  constructor(private nav: Navbarservice,public dataservice: DataservicE) {
    this.dataservice.getstudents().subscribe(students => {
      this.students = [...students];
      this.rows = students;
    });
  }

  ngOnInit() {
    this.nav.show();
  }

  onPage(event: Event) {
    clearTimeout(this.timeout);
    this.timeout = setTimeout(() => {
      console.log('paged!',event);
    },100);
  }

  toggleExpandRow(row) {
    console.log('Toggled Expand Row!',row);
    this.table.rowDetail.toggleExpandRow(row);
  }

  onDetailToggle(event) {
    console.log('Detail Toggled',event);
  }

  updateFilter(event) {
    const val = event.target.value.toLowerCase();
    this.rows = this.students.filter(row =>
      row.AspNetUsers.Nom.toLowerCase().indexOf(val) !== -1 || !val
    );
    this.table.offset = 0;
  }
}

就像在文档代码中一样,我必须在我的输入updateFilter中添加一个函数,它接受输入的值,然后有一个函数根据插入的值过滤临时数组但是这个函数根本不起作用我得不到属性’名称’未定义我使用控制台检查了它们的数组的值并调试它似乎数组是正确的并且有值但我不知道为什么过滤器函数什么都不返回.我尝试添加尝试 – 捕获问题消失但过滤器功能过滤器没有.

编辑：student.component.HTML代码

<div class="container">
  <div class="row">
    <div class="col">
      <form>
        <div class="input-group">
          <input class="form-control" id="search"  name="search" (keyup)='updateFilter($event)' placeholder="Rechercher">
          <div class="input-group-addon"><i class="material-icons">search</i></div>
        </div>
      </form>
    </div>
  </div>
  <div class="row mt-3">
    <div class="col">
      <ngx-datatable
        #myTable
        class='material expandable'
        [columnMode]="'force'"
        [headerHeight]="50"
        [footerHeight]="50"
        [rowHeight]="50"
        [rows]='rows'
        [limit]="20"
        (pagE)="onPage($event)">

        <ngx-datatable-row-detail [rowHeight]="120" #myDetailRow (togglE)="onDetailToggle($event)">
          <ng-template let-row="row" let-expanded="expanded" ngx-datatable-row-detail-template>
            <div class="container">
              <table class="table">
                <tr>
                  <th>Email</th>
                  <td>{{row.AspNetUsers.Email}}</td>
                </tr>
                <tr>
                  <th>adresse</th>
                  <td>{{row.adressE}}</td>
                </tr>
              </table>
            </div>
          </ng-template>
        </ngx-datatable-row-detail>

        <ngx-datatable-column
          [width]="50"
          [resizeable]="false"
          [sortable]="false"
          [draggable]="false"
          [canAutoResize]="false">
          <ng-template let-row="row" let-expanded="expanded" ngx-datatable-cell-template>
            <a
              href="javascript:"
              [class.datatable-icon-right]="!expanded"
              [class.datatable-icon-down]="expanded"
              title="Expand/Collapse Row"
              (click)="toggleExpandRow(row)">
            </a>
          </ng-template>
        </ngx-datatable-column>

        <ngx-datatable-column name="ID" [width]="100">
          <ng-template let-row="row" ngx-datatable-cell-template>
            {{row.studentID}}
          </ng-template>
        </ngx-datatable-column>

        <ngx-datatable-column name="First Name" [width]="100">
          <ng-template let-row="row" ngx-datatable-cell-template>
            {{row.AspNetUsers.NamE}}
          </ng-template>
        </ngx-datatable-column>

        <ngx-datatable-column name="last name" [width]="100">
          <ng-template let-row="row" ngx-datatable-cell-template>
            {{row.AspNetUsers.LastNamE}}
          </ng-template>
        </ngx-datatable-column>

        <ngx-datatable-column name="Special Code" [width]="100">
          <ng-template let-row="row" ngx-datatable-cell-template>
            {{row.AspNetUsers.SpecialCodE}}
          </ng-template>
        </ngx-datatable-column>


        <ngx-datatable-column name="Phonenumber" [width]="100">
          <ng-template let-row="row" ngx-datatable-cell-template>
            {{row.AspNetUsers.Phonenumber}}
          </ng-template>
        </ngx-datatable-column>

      </ngx-datatable>
    </div>
  </div>
</div>

编辑2：
我发现了为什么我得到错误,有一些缺少的名称(它们是null)和内部过滤器,如果它是null,则会发生问题.
我添加了学生！== null但问题仍然存在.