我有一个问题,我的控制台显示错误 *“ ERROR TypeError:无法读取未定义的属性'bg_img_preview'* 。但是结果可以,我可以显示我的数据。不确定,为什么它显示错误事件我可以获取数据。我注意到console.log也不显示结果。我正在使用Angular 7并创建服务HTTP客户端以从本地JSON文件中获取数据
这是服务
import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
@Injectable({providedIn: 'root'})
export class HttpGetJsonService {
private _careerUrl = 'assets/json/careers-page.json';
constructor(private _HttpClient: HttpClient) { }
getCareerData() {
return this._HttpClient.get(this._careerUrl);
}
}
这是职业。ts
import { Component, OnInit } from '@angular/core';
import { HttpGetJsonService } from '../../../shared/http-service/http-
get-json.service';
@Component({
selector: 'app-career-pages',
templateUrl: './career-pages.component.html',
styleUrls: ['./career-pages.component.scss']
})
export class CareerPagesComponent implements OnInit {
section: any = {};
constructor(private _HttpGetJsonService: HttpGetJsonService) { }
ngOnInit() {
this._HttpGetJsonService.getCareerData().subscribe(data => {
this.section = data['data'][0].all_sections;
console.log(this.section);
})
}
}
这是career.html
<div class="col-md-4">
<img [src]="section[2].bg_img_preview" alt="" width="50%">
</div>
这是JSON文件
...........
...........
{
"id": "sec61539669775971",
"name": "career-asset",
"type": null,
"bg_img": "/assets/img/faq-bg/faq-bg-01.jpg",
"bg_color": null,
"created_date": null,
"updated_date": null,
"bg_video": null,
"created_by_id": "usr01539232275296",
"updated_by_id": "usr01539232275296",
"is_backup": 0,
"parent_id": null,
"ordering": 1,
"edit_bg_image": 1,
"site_pages_id": "sitePagesec315395",
"record_type": "asset",
"bg_img_preview": "/assets/img/faq-bg/faq-bg-01.jpg",
"langs": [],
"sub_sections": [],
............
............
结果正常。我可以得到照片,但我想知道为什么会收到该错误?即使console.log也不显示图片值。我对此很陌生。
答案 0 :(得分:2)
您可以尝试:
[src]="section[2]?.bg_img_preview"
在API响应到达之前,您的section[2]
对象没有该值。因此,请使用?
应用空检查,直到响应到达。