小编sou*_*mar的帖子

有人可以指导吗？我收到错误,无法弄清楚为什么？html中的货运变量看起来有问题

app/freightList.component.html:13:8错误尝试diff'[object Object]'

下面是代码

freight.service.ts
=======================

    getFreight (): Promise<Freight[]> {
        return this.http.get(this.freightUrl)
                  .toPromise()
                  .then(this.extractData)
                  .catch(this.handleError);
    }

  private extractData(res: Response) {
      let body = res.json();
      return body || { };
  }

freightList.component.ts
========================
    getFreight() {
        this.freightService
            .getFreight()
            .then(freight => this.freight = freight)
            .catch(error => this.error = error); // TODO: Display error message
    }

freightList.component.html
============================

       <tr *ngFor="let frght of freight">
       <td>{{frght.grp}} - {{frght.grpname}}</td>
       <td>{{frght.subgrp}} - {{frght.subgrpname}}</td>
       <td>{{frght.prodno}} - {{frght.prodname}}</td>
       <td>{{frght.percent}}</td>
       <td>{{frght.effective_date}}</td>
       <td><button (click)="deleteFreight(frght, $event)" class="btn btn-danger btn-sm"><span class="glyphicon glyphicon-remove"></span> Remove</button></td>
       <td><button …