Angular2 如何在 HTML5 模板中显示 localStorage 值? [英] Angular2 How to display localStorage value inside HTML5 template?

问题描述

我在 localStorage 中存储了 2 个键，我想在我的模板中显示其中一个.我无法访问这些值.我什至创建了一个接口来存储 localStorage 中 currentUser 键的值.应该如何实施?

这是当前代码:

服务

import { Injectable } from '@angular/core';从 '@angular/http' 导入 { Http };从 'ts-md5/dist/md5' 导入 { Md5 };从'./user'导入{用户}；导入 'rxjs/add/operator/map';@Injectable()出口类 VehicleService {private defUrl = 'dummy-url.com';构造函数(私有http:Http){}getVehicle(用户名?:字符串，密码?:字符串){const url = (!username || !password) ?this.defUrl : 'dummy-url.com' + 用户名 + '/' + Md5.hashStr(密码);返回 this.http.get(url).map(res => res.json());}parseUser(): 任何 {返回 JSON.parse(localStorage.getItem('parseUser'));}getUser(): 任何 {返回 localStorage.getItem('currentUser');}}

登录组件

import { Component, OnInit } from '@angular/core';从@angular/forms"导入 { FormGroup, FormControl, Validators };从@angular/common"导入{位置}；从@angular/router"导入{路由器}从 './vehicle.service' 导入 { VehicleService };从'./user'导入{用户}；@成分({选择器:'登录'，templateUrl: './login.html',提供者:[车辆服务]})导出类 LoginComponent 实现 OnInit {公共用户:FormGroup；ngOnInit() {this.user = new FormGroup({用户名:new FormControl('', Validators.required),密码:new FormControl('', Validators.required)});}构造函数(公共车辆服务:车辆服务，私有位置:位置，私有路由器:路由器){}提交(用户){this.vehicleService.getVehicle(user.value.username, user.value.password).订阅(用户 => {this.user = 用户；localStorage.setItem('parseUser', JSON.stringify(this.user));this.router.navigate(['/车辆']);console.log('提交');});localStorage.setItem('currentUser', user.value.username);}返回():无效{console.log("返回按钮");this.location.back();}}

车辆组件

import { Component, enableProdMode, OnDestroy } from '@angular/core';从@angular/router"导入{路由器}；从@angular/forms"导入{FormGroup}；从 './vehicle.service' 导入 { VehicleService };从'./user'导入{用户}；import { LoginComponent } from './login.component';enableProdMode();@成分({选择器:'车辆-json'，templateUrl: './vehicle.html',提供者:[车辆服务]})导出类 VehicleComponent 实现 OnDestroy {公共车辆:GeneralVehicle[];公共当前用户:当前用户；ngOnDestroy() {localStorage.removeItem('currentUser');}构造函数(私人车辆服务:车辆服务，私人路由器:路由器){this.vehicleService.getVehicle().subscribe(vehicle => {this.vehicles = 车辆；this.vehicles = this.vehicleService.parseUser();//this.vehicles = this.vehicleService.parseUser();});让 currUser = this.vehicleService.getUser();}toLogin(): void {console.log("登录按钮");this.router.navigate(['/login']);localStorage.removeItem('parseUser');localStorage.removeItem('currentUser');}}接口 GeneralVehicle {状态:编号；达拉斯:车辆[]；}接口车辆{Vehicle_id:编号；达拉斯设置:字符串；达拉斯更新:字符串；dallas_list: 达拉斯列表[];}接口达拉斯列表{数量:数量；认证:号码；}接口当前用户{usr:字符串；}

模板:vehicle.html

<button class="btn btn-default" type="button" (click)="toLogin()">登录</button><div *ngIf="车辆"><b>状态:{{vehicles?.status}} 用户:DISPLAY-USER-HERE</b><div class="list-group" *ngFor="让车辆的车辆.dallases" id="d1"><a class="list-group-item"><h4 class="list-group-item-heading" id="l1">车辆 ID:{{vehicle.vehicle_id}}</h4></a><a class="list-group-item"><h4 class="list-group-item-heading">达拉斯设置:{{vehicle.dallassettings}}</h4></a><a class="list-group-item"><h4 class="list-group-item-heading">达拉斯更新:{{vehicle.dallasupdated}}</h4></a><a class="list-group-item"><h4 class="list-group-item-heading">达拉斯列表:</h4><p class="list-group-item-text" *ngFor="let d of vehicle.dallas_list"><b>编号:</b>{{d.number}}
<b>身份验证:</b>{{d.auth}}</p></a>

解决方案

您可以使用 getter 从 localStorage 获取值并将其显示在您的模板中.在模板的组件类中像下面那样定义它.

get user(): any {返回 localStorage.getItem('currentUser');}

在你的模板中:

<b>状态:{{vehicles?.status}} 用户:{{user}}</b>

I store 2 keys in localStorage and I'd like to display one of them in my template. I can't access these values. I even created an interface just to store the value of the currentUser key from localStorage. How should implement it?

Here's the current code:

Service

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';
import { Md5 } from 'ts-md5/dist/md5';

import { User } from './user';
import 'rxjs/add/operator/map';

@Injectable()
export class VehicleService {
    private defUrl = 'dummy-url.com';

    constructor(private http: Http) { }
    getVehicle(username?: string, password?: string) {
        const url = (!username || !password) ? this.defUrl : 'dummy-url.com' + username + '/' + Md5.hashStr(password);
        return this.http.get(url)
            .map(res => res.json());
    }

    parseUser(): any {
        return JSON.parse(localStorage.getItem('parseUser'));
    }

    getUser(): any {
        return localStorage.getItem('currentUser');
    }
}

Login Component

import { Component, OnInit } from '@angular/core';
import { FormGroup, FormControl, Validators } from '@angular/forms';
import { Location } from '@angular/common';
import { Router } from "@angular/router"

import { VehicleService } from './vehicle.service';
import { User } from './user';

@Component({
    selector: 'login',
    templateUrl: './login.html',
    providers: [VehicleService]
})
export class LoginComponent implements OnInit {
    public user: FormGroup;

    ngOnInit() {
        this.user = new FormGroup({
            username: new FormControl('', Validators.required),
            password: new FormControl('', Validators.required)
        });
    }

    constructor(public vehicleService: VehicleService, private location: Location, private router: Router) {
    }

    onSubmit(user) {
        this.vehicleService
            .getVehicle(user.value.username, user.value.password)
            .subscribe(user => {
                this.user = user;
                localStorage.setItem('parseUser', JSON.stringify(this.user));
                this.router.navigate(['/vehicle']);
                console.log('submit');
            });
        localStorage.setItem('currentUser', user.value.username);
    }

    goBack(): void {
        console.log("Back button");
        this.location.back();
    }
}

Vehicle Component

import { Component, enableProdMode, OnDestroy } from '@angular/core';
import { Router } from '@angular/router';
import { FormGroup } from '@angular/forms';

import { VehicleService } from './vehicle.service';
import { User } from './user';
import { LoginComponent } from './login.component';

enableProdMode();

@Component({
  selector: 'vehicle-json',
  templateUrl: './vehicle.html',
  providers: [VehicleService]
})
export class VehicleComponent implements OnDestroy {
  public vehicles: GeneralVehicle[];
  public currUser: CurrentUser;

  ngOnDestroy() {
    localStorage.removeItem('currentUser');
  }


  constructor(private vehicleService: VehicleService, private router: Router) {
    this.vehicleService.getVehicle().subscribe(vehicle => {
      this.vehicles = vehicle;
      this.vehicles = this.vehicleService.parseUser();
      //this.vehicles = this.vehicleService.parseUser();
    });
    let currUser = this.vehicleService.getUser();
  }

  toLogin(): void {
    console.log("toLogin button");
    this.router.navigate(['/login']);
    localStorage.removeItem('parseUser');
    localStorage.removeItem('currentUser');
  }

}

interface GeneralVehicle {
  status: number;
  dallases: Vehicle[];
}

interface Vehicle {
  vehicle_id: number;
  dallassettings: string;
  dallasupdated: string;
  dallas_list: DallasList[];
}

interface DallasList {
  number: number;
  auth: number;
}

interface CurrentUser {
  usr: string;
}

Template: vehicle.html

<button class="btn btn-default" type="button" (click)="toLogin()">Login</button>
<div *ngIf="vehicles">
    <b>Status: {{vehicles?.status}} for user: DISPLAY-USER-HERE</b>
    <div class="list-group" *ngFor="let vehicle of vehicles.dallases" id="d1">
        <a class="list-group-item">
            <h4 class="list-group-item-heading" id="l1">Vehicle ID: {{vehicle.vehicle_id}}</h4>
        </a>
        <a class="list-group-item">
            <h4 class="list-group-item-heading">Dallas settings: {{vehicle.dallassettings}}</h4>
        </a>
        <a class="list-group-item">
            <h4 class="list-group-item-heading">Dallas updated: {{vehicle.dallasupdated}}</h4>
        </a>
        <a class="list-group-item">
            <h4 class="list-group-item-heading">Dallas list:</h4>
            <p class="list-group-item-text" *ngFor="let d of vehicle.dallas_list">
                <b>Number:</b> {{d.number}}<br>
                <b>Auth:</b> {{d.auth}}</p>
        </a>
    </div>
</div>

解决方案

You can use a getter to get the value from localStorage and show it in your template. Define it like bellow in the component class of your template.

get user(): any {
    return localStorage.getItem('currentUser');
}

In you template:

<b>Status: {{vehicles?.status}} for user: {{user}}</b>

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