Javascript 连接展平数据
我想将客户表中init上的数据加入到项目列表中 模型是这样的:Javascript 连接展平数据,javascript,angular,firebase-realtime-database,angularfire2,Javascript,Angular,Firebase Realtime Database,Angularfire2,我想将客户表中init上的数据加入到项目列表中 模型是这样的: 计划 钥匙 名称:string 客户:customerKey 顾客 钥匙 名称:string 你有没有一个例子,我是如何使用angularfire2从angular2组件实现这一点的 我的控制器如下所示: import { Component, OnInit } from '@angular/core'; import { Project } from '../project'; import { Router } fr
- 计划
- 钥匙
- 名称:string
- 客户:customerKey
- 顾客
- 钥匙
- 名称:string
import { Component, OnInit } from '@angular/core';
import { Project } from '../project';
import { Router } from '@angular/router';
import { FirebaseAuth } from 'angularfire2';
import { AngularFire, FirebaseListObservable, FirebaseObjectObservable } from 'angularfire2';
import { Observable } from 'rxjs';
@Component({
moduleId: module.id,
selector: 'app-projects',
templateUrl: 'projects.component.html',
styleUrls: ['projects.component.css']
})
export class ProjectsComponent implements OnInit {
projects: FirebaseListObservable<any[]>;
customers: FirebaseListObservable<any[]>;
projectName: string;
constructor(
private router: Router,
private af: AngularFire
) { };
ngOnInit() {
this.projects = this.af.database.list('projects');
}
add(projectName: string) {
this.af.database.list('projects')
.push({ name: projectName, id: '123' });
this.projectName = null;
}
}
ngOnInit() {
this.projects = this.af.database.list(`projects`)
.map(projects => {
projects.map(project => {
this.af.database.object('customer/' + project.customer + '/name')
.subscribe(customer => {
project.customer = customer;
})
return project;
})
return projects;
});
}
- projects
- key
- name: string
- customers
- customerKey: boolean
- customers
- key
- name: string
现在,我无法从中的模板访问customer的name属性
<li *ngFor="let project of projects | async">
project.customer.$value
项目。客户。$value
不太清楚您的数据集是什么样子,所以我只想写一个基本示例。假设这样的结构:
import { Component, OnInit } from '@angular/core';
import { Project } from '../project';
import { Router } from '@angular/router';
import { FirebaseAuth } from 'angularfire2';
import { AngularFire, FirebaseListObservable, FirebaseObjectObservable } from 'angularfire2';
import { Observable } from 'rxjs';
@Component({
moduleId: module.id,
selector: 'app-projects',
templateUrl: 'projects.component.html',
styleUrls: ['projects.component.css']
})
export class ProjectsComponent implements OnInit {
projects: FirebaseListObservable<any[]>;
customers: FirebaseListObservable<any[]>;
projectName: string;
constructor(
private router: Router,
private af: AngularFire
) { };
ngOnInit() {
this.projects = this.af.database.list('projects');
}
add(projectName: string) {
this.af.database.list('projects')
.push({ name: projectName, id: '123' });
this.projectName = null;
}
}
ngOnInit() {
this.projects = this.af.database.list(`projects`)
.map(projects => {
projects.map(project => {
this.af.database.object('customer/' + project.customer + '/name')
.subscribe(customer => {
project.customer = customer;
})
return project;
})
return projects;
});
}
- projects
- key
- name: string
- customers
- customerKey: boolean
- customers
- key
- name: string
示例数据
- projects
- projectId1
- name: "Cool project!",
- customers
- customerId1: true,
- customerId2: true
- projectId2
- name: "Another cool project!",
- customers
- customerId2: true,
- customerId3: true
- customers
- customerId1
- name: "John Smith"
- customerId2
- name: "John Doe"
- customerId3
- name: "John John"
因此,我们在每个项目的customers
属性中存储客户的密钥
假设我们想列出每个项目,但我们还想获得客户的真实姓名,而不仅仅是他们的id。由于firebase没有加入,我们将不得不手动执行此操作。这里有一种方法:
this.projects = this.af.database.list(`projects`)
.map(projects => {
return projects.map(project => {
project.customers.map(customer => {
this.af.database.list(`customers`)
.subscribe(c => {
customer = c;
});
});
return project;
});
});
如果您想异步获取数据(在本例中,使用模板中的
async
管道),可以将内部.subscribe
更改为简单的.map
。您可以通过显示模板或更好的方式创建plnkr来提供更多上下文吗?嗨,大卫,刚刚在文章中添加了模型描述。模板内部没有什么特别的->“让项目中的项目|异步”。我的问题是,如何从customers表中获取相关的customer.name,同时从“projects”流式传输数据,并将this.project.customer设置为此值谢谢您的回复。确切地说,项目中的customer字段只是对customers表中customer记录的引用。不幸的是,如果我使用您的代码类型“Observable”,则抱怨FirebaseListObservable类型的typescript不能分配给类型“FirebaseListObservable”。类型“Observable”中缺少属性“\u ref”。您可以将FirebaseListObservable
类型更改为Observable
,它应该可以工作。+1到@JohnSmith。这是我们正在处理的库的最新问题,它仍处于测试阶段,所以请注意:)而且您还可以获得project.customers.map
不是函数错误。有人解决了这个问题吗?导入map
操作符<代码>导入'rxjs/add/operator/map'代码>