属性'id‘在类型'void’上不存在

Question

我正在尝试为我的angular应用程序的所有操作实现一个审计跟踪，比如'delete‘'addUser’'update‘等。我能够用“post blog”函数成功地实现这一点，该函数位于“post-dashboard.Component.ts”中，现在我正尝试使用'delete user’函数执行相同的操作，但编译器返回错误“属性'id‘不存在于类型'void'”。

我尝试将id定义为'id: any;‘和'id =’‘，但我不认为这是解决方案。错误不会消失。审计跟踪功能应该在控制台中打印输出(审计跟踪)，并在审计跟踪模型下将审计跟踪日志存储在数据库中

这是我的学生-user.Component.ts。注意deleteStudent(value)函数……这就是我要实现它的地方

import { Component, OnInit } from '@angular/core';
import { map, catchError} from 'rxjs/operators';
import {FirebaseService} from '../services/firebase.service';
import {Router} from '@angular/router';
import { AngularFirestore} from "angularfire2/firestore";
import { Observable } from 'rxjs';
import { AuditTrailService } from 'src/app/services/audit-trail/audit-trail.service';
import { AngularFireStorage } from '@angular/fire/storage';


@Component({
  selector: 'app-student-user',
  templateUrl: './student-user.component.html',
  styleUrls: ['./student-user.component.scss']
})

export class StudentUserComponent implements OnInit{
  students: any;
  students_data :any;
  public searchString: string;
  response: any;
  is_loading: any;
  ideas; any;
  term = '';
  //id: any[];


  constructor(
    public firebaseService: FirebaseService,
    private router: Router,
    public db: AngularFirestore,
    private storage: AngularFireStorage,
    public _auditTrailService:AuditTrailService
  ) { }


 ngOnInit() {

  this.getStudents()
  this.searchStudents(event)

}


getStudents() {
  this.students_data = this.db.collection('User', ref => ref.where('role', '==', 'student')).snapshotChanges().pipe(map(changes => {

  return changes.map(a => {
  const data: any = a.payload.doc.data();
  data.id = a.payload.doc.id;
  return data;
  });
  })
  );

  this.students_data.subscribe(
  res => {
  console.log(res);
  this.students = res;
  //this.blogs_snapshot = res;
  });

  }

  searchStudents(event){
    if (event.key === "Enter"){
      console.log(this.term)
      this.db.collection('User', ref => ref.where('full_name', '==', this.term)).valueChanges().subscribe(
      res => {
      this.response = res;
      console.log(this.response);

      this.ideas = res;
      this.is_loading = false;
        }
        );
    }
  }

  deleteStudent(value){
    this.db.collection('User').doc(value).delete().then( 
      res =>{
      console.log(res)
      this.students = res;
      const _audit_trail = {
        'action' : ' has deleted a student ',
        'object': res.id,
        'created_at': new Date(),
        'user':{
          'id': '4545454545454545454',
          'email':'daanyu@gmail.com' }
         } 
      console.log(_audit_trail)

      this._auditTrailService.createAuditTrailLog(_audit_trail)

    },

    err=>{
      console.log(err)
    }
    )
  }

} 

这是我的错误。

ERROR in src/app/student-user/student-user.component.ts(87,23): error TS2339: Property 'id' does not exist on type 'void'.

我正在使用Firebase作为我的数据库，这是我期望在我的审计跟踪模型下的数据库中返回的内容：

操作“已删除学生”电子邮件2019年7月22日下午5:49:33 UTC+3用户: created_at "daanyu@gmail.com“id "4545454545454545454”

Answer 1

我以前没有使用过Firebase，但是你的错误让我相信Firestore中的delete()方法不会返回成功响应，因为它暗示res是void类型的。您可以根据自己的用例使用this.students或this.response中的id。