Angular X中使用ngrx的方法详解(附源码)
前言
ngrx 是 angular框架的状态容器,提供可预测化的状态管理。下面话不多说,来一起看看详细的介绍:
1.首先创建一个可路由访问的模块 这里命名为:demopetmodule。
包括文件:demopet.html、demopet.scss、demopet.component.ts、demopet.routes.ts、demopet.module.ts
代码如下:
demopet.html
<!--暂时放一个标签--> <h1>demo</h1>
demopet.scss
h1{ color:#d70029; }
demopet.component.ts
import { component} from '@angular/core'; @component({ selector: 'demo-pet', styleurls: ['./demopet.scss'], templateurl: './demopet.html' }) export class demopetcomponent { //nothing now... }
demopet.routes.ts
import { demopetcomponent } from './demopet.component'; export const routes = [ { path: '', pathmatch: 'full', children: [ { path: '', component: demopetcomponent } ] } ];
demopet.module.ts
import { commonmodule } from '@angular/common'; import { formsmodule } from '@angular/forms'; import { ngmodule } from '@angular/core'; import { routermodule } from '@angular/router'; import { routes } from './demopet.routes'; @ngmodule({ declarations: [ demopetcomponent, ], imports: [ commonmodule, formsmodule, routermodule.forchild(routes) ], providers: [ ] }) export class demopetmodule { }
整体代码结构如下:
运行效果如下:只是为了学习方便,能够有个运行的模块
2.安装ngrx
npm install @ngrx/core --save npm install @ngrx/store --save npm install @ngrx/effects --save
@ngrx/store是一个旨在提高写性能的控制状态的容器
3.使用ngrx
首先了解下单向数据流形式
代码如下:
pet-tag.actions.ts
import { injectable } from '@angular/core'; import { action } from '@ngrx/store'; @injectable() export class pettagactions{ static load_data='load data'; loaddata():action{ return { type:pettagactions.load_data }; } static load_data_success='load data success'; loaddtasuccess(data):action{ return { type:pettagactions.load_data_success, payload:data }; } static load_info='load info'; loadinfo():action{ return { type:pettagactions.load_info }; } static load_info_success='load info success'; loadinfosuccess(data):action{ return { type:pettagactions.load_info_success, payload:data }; } }
pet-tag.reducer.ts
import { action } from '@ngrx/store'; import { observable } from 'rxjs/observable'; import { pettagactions } from '../action/pet-tag.actions'; export function pettagreducer(state:any,action:action){ switch(action.type){ case pettagactions.load_data_success:{ return action.payload; } // case pettagactions.load_info_success:{ // return action.payload; // } default:{ return state; } } } export function inforeducer(state:any,action:action){ switch(action.type){ case pettagactions.load_info_success:{ return action.payload; } default:{ return state; } } }
note:action中定义了我们期望状态如何发生改变 reducer实现了状态具体如何改变
action与store之间添加ngrx/effect 实现action异步请求与store处理结果间的解耦
pet-tag.effect.ts
import { injectable } from '@angular/core'; import { effect,actions } from '@ngrx/effects'; import { pettagactions } from '../action/pet-tag.actions'; import { pettagservice } from '../service/pet-tag.service'; @injectable() export class pettageffect { constructor( private action$:actions, private pettagaction:pettagactions, private service:pettagservice ){} @effect() loaddata=this.action$ .oftype(pettagactions.load_data) .switchmap(()=>this.service.getdata()) .map(data=>this.pettagaction.loaddtasuccess(data)) @effect() loadinfo=this.action$ .oftype(pettagactions.load_info) .switchmap(()=>this.service.getinfo()) .map(data=>this.pettagaction.loadinfosuccess(data)); }
4.修改demopet.module.ts 添加 ngrx支持
import { storemodule } from '@ngrx/store'; import { effectsmodule } from '@ngrx/effects'; import { pettagactions } from './action/pet-tag.actions'; import { pettagreducer,inforeducer } from './reducer/pet-tag.reducer'; import { pettageffect } from './effect/pet-tag.effect';
@ngmodule({ declarations: [ demopetcomponent, ], imports: [ commonmodule, formsmodule, routermodule.forchild(routes), //here new added storemodule.providestore({ pet:pettagreducer, info:inforeducer }), effectsmodule.run(pettageffect) ], providers: [ pettagactions, pettagservice ] }) export class demopetmodule { }
5.调用ngrx实现数据列表获取与单个详细信息获取
demopet.component.ts
import { component, oninit, viewchild, afterviewinit } from '@angular/core'; import { observable } from "rxjs"; import { store } from '@ngrx/store'; import { subscription } from 'rxjs/subscription'; import { httpservice } from '../shared/services/http/http.service'; import { pettag } from './model/pet-tag.model'; import { pettagactions } from './action/pet-tag.actions'; @component({ selector: 'demo-pet', styleurls: ['./demopet.scss'], templateurl: './demopet.html' }) export class demopetcomponent { private sub: subscription; public dataarr: any; public dataitem: any; public language: string = 'en'; public param = {value: 'world'}; constructor( private store: store<pettag>, private action: pettagactions ) { this.dataarr = store.select('pet'); } ngoninit() { this.store.dispatch(this.action.loaddata()); } ngondestroy() { this.sub.unsubscribe(); } info() { console.log('info'); this.dataitem = this.store.select('info'); this.store.dispatch(this.action.loadinfo()); } }
demopet.html
<h1>demo</h1> <pre> <ul> <li *ngfor="let d of dataarr | async"> demo : {{ d.msg }} <button (click)="info()">info</button> </li> </ul> {{ dataitem | async | json }} <h1 *ngfor="let d of dataitem | async"> {{ d.msg }} </h1> </pre>
6.运行效果
初始化时候获取数据列表
点击info按钮 获取详细详细
7.以上代码是从项目中取出的部分代码,其中涉及到httpservice需要自己封装,data.json demo.json两个测试用的json文件,名字随便取的当时。
http.service.ts
import { inject, injectable } from '@angular/core'; import { http, response, headers, requestoptions, urlsearchparams } from '@angular/http'; import { observable } from "rxjs"; import 'rxjs/add/operator/map'; import 'rxjs/operator/delay'; import 'rxjs/operator/mergemap'; import 'rxjs/operator/switchmap'; import 'rxjs/add/operator/catch'; import 'rxjs/add/observable/throw'; import { handleerror } from './handleerror'; import { rootpath } from './http.config'; @injectable() export class httpservice { private _root: string=""; constructor(private http: http) { this._root=rootpath; } public get(url: string, data: map<string, any>, root: string = this._root): observable<any> { if (root == null) root = this._root; let params = new urlsearchparams(); if (!!data) { data.foreach(function (v, k) { params.set(k, v); }); } return this.http.get(root + url, { search: params }) .map((resp: response) => resp.json()) .catch(handleerror); } }
8.模块源代码
总结
以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作能带来一定的帮助,如果有疑问大家可以留言交流,谢谢大家对的支持。
上一篇: jQuery实现拼图小游戏(实例讲解)