ProjectDetailsComponent.html:18错误TypeError:无法读取未定义的属性'id'

时间:2019-11-06 16:41:04

标签: django angular angular8 angular-observable

我已经在Django中构建了RestApi,并在localhost:8000/project/listproject-details的{​​{1}}接收了JSON响应

我还创建了用于接收JSON数据的相应服务,类和组件。我还能够获取localhost:8000/project/details/:idproject_list

当我执行GET project_details时,它会给出DATA的JSON响应,但也会在运行时给出此错误。

  

“ ProjectDetailsComponent.html:18错误TypeError:无法读取未定义的属性'id'。”

project.ts(类)

Project_detials

ProjectDetailsComponent.ts(组件)

export class Project_list {
    id : number;
    projectname : string;
}
export class Project_details {
    id : number;
    projectname : string;
    project_status : string;
    description : string;
    start_date : Date;
    due_date : Date;
}
```

# project.service.ts (Service)
```
import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';
import { Project_list,Project_details } from '../models/project';
import { Observable } from 'rxjs';


@Injectable({
  providedIn: 'root'
})
export class ProjectService {
  private projectUrl: string;

  constructor(private http: HttpClient) { 
    this.projectUrl = 'http://localhost:8000/project';
  }

  public findAllProjects(): Observable<Project_list[]>
   {
     return this.http.get<Project_list[]>(this.projectUrl+'/list');
   }

   public findProjectById(id:number) : Observable<any>
   {
     return this.http.get<Project_details>(this.projectUrl+'/details/'+id+'/');
   } 
}
```

# ProjectListComponent.ts (Component)
```
import { Component, OnInit } from '@angular/core';
import { ProjectService } from '../../../services/project.service'
import { Project_list } from '../../../models/project'

@Component({
  selector: 'app-project-list',
  templateUrl: './project-list.component.html',
  styleUrls: ['./project-list.component.css']
})
export class ProjectListComponent implements OnInit {
  project_list : Project_list[];
  constructor( private projectService:ProjectService ) { }

  ngOnInit() {
    this.projectService.findAllProjects().subscribe(data => {
      this.project_list = data;
      console.log(data);
    });
  }

}

ProjectDetailsComponent.html(HTML)

import { Component, OnInit } from '@angular/core';
import { ProjectService } from '../../../services/project.service';
import {Project_details} from '../../../models/project';
import { ActivatedRoute } from '@angular/router';

@Component({
  selector: 'app-project-details',
  templateUrl: './project-details.component.html',
  styleUrls: ['./project-details.component.css']
})
export class ProjectDetailsComponent implements OnInit {
  project_details : Project_details;
  id:number;
  private sub:any;

  constructor(private projectService:ProjectService, private route: ActivatedRoute) { }
  ngOnInit() {

    this.sub = this.route.params.subscribe(params => {
    this.id = +params['id'];
    console.log(this.id);
    });

    this.projectService.findProjectById(this.id).subscribe(data => {
    this.project_details = data;
    console.log(this.project_details);
    });
  }

}

1 个答案:

答案 0 :(得分:0)

还可以粘贴API响应中返回的JSON对象吗?

Django可能会发送数据数组。 请尝试(在ProjectDetailsComponent.ts(组件)中) this.project_details = data[0]; 装的 this.project_details = data;