day05 Router、vuex、axios

配置

router和vuex需要在创建vue项目的时候，开始的时候选择Manually select features，于是就可以在下一个创建配置讯问中选择router和vuex。

axios则需要执行命令行：

npm install axios -S

之后再在需要发送请求的view导入即可。

router实现左边点击右边打开

首先需要安装ElementUI，方法见day4 vue2以及ElementUI-CSDN博客。

在App.vue中导入框架，将<nav>、<router-view>标签移动到对应位置。其中to配置相当于servlet请求的路径。

<template><div id="app"><el-container><el-header>欢迎你</el-header><el-container><el-aside width="200px"><nav><ul><li><router-link to="/">Home</router-link></li><li><router-link to="/about">About</router-link></li><li><router-link to="/question">问题管理</router-link></li><li><router-link to="/new">新页面</router-link></li></ul></nav></el-aside><el-main><router-view/></el-main></el-container></el-container></div>
</template><style>
#app {font-family: Avenir, Helvetica, Arial, sans-serif;-webkit-font-smoothing: antialiased;-moz-osx-font-smoothing: grayscale;text-align: center;color: #2c3e50;
}nav {padding: 30px;
}nav a {font-weight: bold;color: #2c3e50;
}nav a.router-link-exact-active {color: #42b983;
}
</style>

并在router的 index.js中配置请求路径对应的view们，相当于web.xml。其中有两种方式导入view，第一种可以直接开头import，在routers中的component中就只用写出你的模块名即可，这是静态导入，其实相当于js中的include编译指令，开始就导入自然加载速度会变快，但是动态导入往往常见一些，就比如这里可以直接在component中 ()=>import ('路径')，这样是动态导入，请求该view的时候才会加载，更灵活。

import Vue from 'vue'
import VueRouter from 'vue-router'
import HomeView from '../views/HomeView.vue'
// 路由的配置
Vue.use(VueRouter)const routes = [{path: '/',name: 'home',component: HomeView},{path: '/about',name: 'about',// route level code-splitting// this generates a separate chunk (about.[hash].js) for this route// which is lazy-loaded when the route is visited.component: () => import(/* webpackChunkName: "about" */ '../views/AboutView.vue')},{path:'/question',name:'question',component:() => import(/* webpackChunkName: "about" */ '../views/QuestionView.vue')},{path:'/new',name:'new',component:() => import(/* webpackChunkName: "about" */ '../views/NewView.vue')}
]
// js文件中导出一个 router 实例
const router = new VueRouter({routes
})export default router

使用vuex处理用户的动作

vuex主要往外导出五个属性，在store的index.js中，state用于储存页面共享的数据，actions用于处理发出的动作，mutations用于直接操纵state中的数据，getters中对state中的数据进行再次加工，类似vue中计算属性computed。

就如图片中一样，view中用dispatch发出动作，actions使用commit将动作处理，转给mutations对state进行直接操作，前端可以直接调用state中的数据，来实现数据更新。getters的处理则直接可以前端执行{{$store.getters.方法名}}。

 store中的index.js：

import Vue from 'vue'
import Vuex from 'vuex'Vue.use(Vuex)export default new Vuex.Store({state: {// 共享数据count: 0, // 初值为零myNewList:[]},getters: { // 对state中的数据进行再次加工，类似vue中计算属性computedupdate(state) {return state.count * 10;}},mutations: { // 修改state数据change(state, value) {state.count += value;},sub(state, value) {state.count -= value;}},actions: { // 相应动作处理// 必须与dispatch中的时间名一致sum(context, value) {context.commit('change', value);},sub(context, value) {context.commit('sub', value);}},modules: { // 分模块化开发，一个模块可以有自己的state，getters，mutations，actions}
})

前端调用：

<template><div class="about"><h1>This is an about page</h1><h2>当前计算的和为：{{$store.state.count}}</h2><h2>当前计算的和 ✖ 10 为：{{$store.getters.update}}</h2><el-button @click="add" type="primary" round>我猜你不会点击我</el-button><br/><br/><el-button @click="sub" type="primary" round>我可以回去哦</el-button></div>
</template>
<script>
export default{name: "AboutView",methods:{// 求和时间处理add(){// 进行dispatchthis.$store.dispatch("sum",5);},sub(){this.$store.dispatch("sub",10);}}
}
</script>

使用axios实现前后端连接

其原理是可以使用axios访问不同端口，向不同端口发送请求，有两种方式发送请求：

可以直接在view中导入axios包，直接发送请求，但是因为请求的地址往往容易变化，所以需要用第二种方式来发送请求，首先在util包中创建js页面配置baseUrl（在此导入axios包），也就是端口号，然后在api包中创建针对不同view的不同请求url，也就是请求的具体地址和请求方法以及可能的参数，将方法配置可以其他文件访问（export default），这时候就需要将配置好的js文件直接导入到view中，然后再调用方法即可。

url在view中（第一种）：

<template><div class="home"><img alt="Vue logo" src="../assets/logo.png" /><HelloWorld msg="Welcome to Your Vue.js App" /><br/><el-button @click="sendRequest()" type="primary">发送axios请求，进行调用springboot项目</el-button><br/><br/><br/><el-table :data="this.$store.state.myNewList" border style="width: 100%"><el-table-column fixed prop="id" label="编号" width="150"></el-table-column><el-table-column prop="expertName" label="专家姓名" width="120"> </el-table-column><el-table-column prop="questioner" label="提问人" width="120"></el-table-column><el-table-column prop="phone" label="电话" width="120"> </el-table-column><el-table-column prop="plantName" label="农作物名称" width="300"></el-table-column><el-table-column prop="question" label="问题" width="120"> </el-table-column><el-table-column prop="answer" label="回答" width="120"> </el-table-column><el-table-column prop="status" label="状态" width="120"> </el-table-column><el-table-column fixed="right" label="操作" width="100"><template slot-scope="scope"><el-button @click="handleClick(scope.row)" type="text" size="small">查看</el-button><el-button type="text" size="small">编辑</el-button></template></el-table-column></el-table></div>
</template><script>
// @ is an alias to /src
import HelloWorld from "@/components/HelloWorld.vue";
import axios from "axios"; // 引入axios库export default {name: "HomeView",components: {HelloWorld,},methods: {sendRequest() {axios.get("http://localhost:8888/question/findAll").then(response => {this.questonList = response.data.data;this.$store.state.myNewList = response.data.data;});},},data(){return {questonList: []}}
};
</script>

url在js文件中（第二种）：

<template><div class="home"><img alt="Vue logo" src="../assets/logo.png" /><br /><el-button @click="search" type="primary">search</el-button><el-button @click="add()" type="primary">add</el-button><br /><br /><br /><el-input v-model="inputValue" placeholder="请输入id或专家姓名"></el-input><br /><br /><el-table :data="questionList" border style="width: 100%"><el-table-column fixed prop="id" label="编号" width="150"></el-table-column><el-table-column prop="expertName" label="专家姓名" width="120"></el-table-column><el-table-column prop="questioner" label="提问人" width="120"></el-table-column><el-table-column prop="phone" label="电话" width="120"> </el-table-column><el-table-column prop="plantName" label="农作物名称" width="300"></el-table-column><el-table-column prop="question" label="问题" width="120"></el-table-column><el-table-column prop="answer" label="回答" width="120"></el-table-column><el-table-column prop="status" label="状态" width="120"></el-table-column><el-table-column fixed="right" label="操作" width="100"><template slot-scope="scope"><el-button @click="handleClick(scope.row)" type="text" size="small">删除</el-button><el-button type="text" size="small">编辑</el-button></template></el-table-column></el-table></div>
</template><script>
// @ is an alias to /src
import queApi from "@/api/question"; // 导入封装后的axios请求，具体见src/api/question.jsexport default {name: "HomeView",methods: {sendRequest() {queApi.getQuestionList().then((res) => {this.questionList = res.data.data;this.$store.state.myNewList = this.questionList; // 数据共享});}},data() {return {questionList: [],inputValue: "",};},
};
</script>

api文件中配置：

import request from '../utils/request'; // 导入axios实例/*** 调用boot端，进行/question/findAll查询* @returns {Promise}*/
function getQuestionList() { // 获取问题列表return request({url: '/question/findAll',method: 'get'});
}export default {getQuestionList, // 导出函数
} // 导出对象

除了findAll方法之外，还可以其他方法：

后端

注意axios支持get、post、put、delete等请求，所以可以直接按照swagger的请求规范做，还有一点要注意，需要配置后端可以接受并处理其他端口发出的各种请求，也就需要配置CorsConfig文件：

package com.zheng.config;import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;@Configuration
public class CorsConfig implements WebMvcConfigurer {@Overridepublic void addCorsMappings(CorsRegistry registry) {// 添加映射路径registry.addMapping("/**")// .allowedOrigins("*") //.allowedOriginPatterns("*") //允许哪些域的请求，星号代表允许所有.allowedMethods("POST", "GET", "PUT", "OPTIONS", "DELETE") // 允许的方法.allowedHeaders("*") // 允许的头部设置.allowCredentials(true) // 是否发送cookie.maxAge(168000); // 预检间隔时间}}

除此之外，如果发送的是post、put请求，也就是要将传递的参数放到请求体中的，需要在获得形参之前加@RequestBody，才能将传递的参数和需要的参数一一对应。

package com.zheng.controller;import com.zheng.entity.Question;
import com.zheng.model.Result;
import com.zheng.service.QuestionService;
import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.tags.Tag;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;import java.util.List;/*** Controller整合Swagger*/
@RestController
@RequestMapping("/question")
@Tag(name="question",description = "tb_question控制层") // swagger标签
public class QuestionController {@Autowiredprivate QuestionService questionService;@Operation(description = "question查询全部") // swagger 标签@GetMapping("/findAll")
//    public List<Question> findAll() {
//        return questionService.findAll();
//    }public Result<List<Question>> findAll() {return Result.ok(questionService.findAll());}/*** findById?id=10* @param id* @return*/@Operation(description = "question根据主键查询") // swagger 标签@GetMapping("findById")
//    public Question findById(@RequestParam("id") int id) {
//        return questionService.findById(id);
//    }public Result<Question> findById(@RequestParam("id") int id) {return Result.ok(questionService.findById(id));}@Operation(description = "根据专家名字查询")@GetMapping("/findByExpertName/{expertName}")public Result<List<Question>> findByExpertName(@PathVariable("expertName") String expertName) {return Result.ok(questionService.findByExpertName(expertName));}@PostMapping("/save")@Operation(description = "添加question")public Result<Integer> save(@RequestBody Question question) {return Result.ok(questionService.save(question));}@PutMapping("/update") // 修改只能用put请求，删除只能用delete请求@Operation(description = "修改question")public Result<Integer> update(Question question) {return Result.ok(questionService.update(question));}/*** /delete/10* @param id* @return*/@DeleteMapping("/delete/{qid}")@Operation(description = "按照编号删除question")public Result<Integer> delete(@PathVariable("qid") int id) {return Result.ok(questionService.delete(id));}
}

一个好习惯是将返回的数据封装成一个Result<T>类（这也相当于一个特殊的实体类）来处理，这样当面对不同的数据类型的时候才能正常处理：

package com.zheng.model;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.ToString;@Data
@NoArgsConstructor
@AllArgsConstructor
@ToString
public class Result<T> {private Integer code; // 编码 ；200 404 500private String msg; // 消息内容private T data; // 真正的数据public Result(Integer code, T data) {this.code = code;this.data = data;}public Result(String msg, T data) {this.msg = msg;this.data = data;}public Result(T data){this.data = data;}public static<T> Result<T> ok(T data){return new Result(200,"success",data);}public static<T> Result<T> fail(Integer code){return new Result(500,"fail",null);}
}

前端

对于前端如何链接这么多方法呢：

如果是get、delete请求并将传递的参数直接拼接在路径中，而非键值对的形式，那么在前端也可以直接拼接在url中，不能使用参数params，否则404：

function findByExpertName(expertName) {return request({url:'/question/findByExpertName/' + expertName,method:'get'})
}

 对于post请求可以直接这样传递参数（在控制层是直接接受一个对象的类型，所以传入的也是一个对象类型，直接使用data列出要传递的参数即可），对于get、delete请求参数必须params，而post、put请求必须data传递数据：

function addQuestion(data) { // 新增问题return request({url: '/question/save',method: 'post', // post 请求执行添加操作data: data // 发送数据})
}

最后，做的小项目：实现findById以及findByExpertName以及add方法

<template><div class="home"><img alt="Vue logo" src="../assets/logo.png" /><br /><el-button @click="search" type="primary">search</el-button><el-button @click="add()" type="primary">add</el-button><br /><br /><br /><el-input v-model="inputValue" placeholder="请输入id或专家姓名"></el-input><br /><br /><el-table :data="questionList" border style="width: 100%"><el-table-column fixed prop="id" label="编号" width="150"></el-table-column><el-table-column prop="expertName" label="专家姓名" width="120"></el-table-column><el-table-column prop="questioner" label="提问人" width="120"></el-table-column><el-table-column prop="phone" label="电话" width="120"> </el-table-column><el-table-column prop="plantName" label="农作物名称" width="300"></el-table-column><el-table-column prop="question" label="问题" width="120"></el-table-column><el-table-column prop="answer" label="回答" width="120"></el-table-column><el-table-column prop="status" label="状态" width="120"></el-table-column><el-table-column fixed="right" label="操作" width="100"><template slot-scope="scope"><el-button @click="handleClick(scope.row)" type="text" size="small">删除</el-button><el-button type="text" size="small">编辑</el-button></template></el-table-column></el-table><!--  添加的对话框--><el-dialog title="问题信息" :visible.sync="dialogFormVisible"><el-form :model="form" :rules="rules" ref="questionForm"><el-form-itemlabel="expertName":label-width="formLabelWidth"prop="expertName"><el-input v-model="form.expertName" autocomplete="off"></el-input></el-form-item><el-form-itemlabel="questioner":label-width="formLabelWidth"prop="questioner"><el-input v-model="form.questioner" autocomplete="off"></el-input></el-form-item><el-form-item label="phone" :label-width="formLabelWidth" prop="phone"><el-input v-model="form.phone" autocomplete="off"></el-input></el-form-item><el-form-itemlabel="plantName":label-width="formLabelWidth"prop="plantName"><el-input v-model="form.plantName" autocomplete="off"></el-input></el-form-item><el-form-item label="title" :label-width="formLabelWidth" prop="title"><el-input v-model="form.title" autocomplete="off"></el-input></el-form-item><el-form-itemlabel="question":label-width="formLabelWidth"prop="question"><el-input v-model="form.question" autocomplete="off"></el-input></el-form-item><el-form-itemlabel="answer":label-width="formLabelWidth"prop="answer"><el-input v-model="form.answer" autocomplete="off"></el-input></el-form-item><el-form-itemlabel="status":label-width="formLabelWidth"prop="status"><el-input v-model="form.status" autocomplete="off"></el-input></el-form-item></el-form><div slot="footer" class="dialog-footer"><el-button @click="cancel">取 消</el-button><el-button type="primary" @click="save">保 存</el-button></div></el-dialog></div>
</template><script>
// @ is an alias to /src
import queApi from "@/api/question"; // 导入封装后的axios请求，具体见src/api/question.jsexport default {name: "HomeView",methods: {sendRequest() {queApi.getQuestionList().then((res) => {this.questionList = res.data.data;this.$store.state.myNewList = this.questionList;});},isNumber(value) {return /^\d+$/.test(value) && value !== '';},search() {if (this.inputValue == "") {this.sendRequest();} else {if (this.isNumber(this.inputValue)) {this.findById();} else {this.findByExpertName();}}//   this.sendRequest();},findById() {queApi.findById(this.inputValue).then((res) => {this.question = res.data.data;if (this.question != null) {this.$set(this, "questionList", []); // 清空原有数据this.questionList.push(this.question);} else {alert("未查询到数据");}});},add() {this.dialogFormVisible = true;},cancel() {this.dialogFormVisible = false;this.form = {expertName: "",questioner: "",phone: "",plantName: "",title: "",question: "",answer: "",status: "",};},save() {// 验证表单this.$refs.questionForm.validate((validate) => {if (validate) {// 验证通过，可以提交数据//   alert(this.form.expertName);queApi.addQuestion(this.form).then((res) => {if (res.data.code == 200) {alert("添加了" + res.data.data + "条数据");this.sendRequest();} else {alert(res.data.msg);}});this.dialogFormVisible = false;this.form = {expertName: "",questioner: "",phone: "",plantName: "",title: "",question: "",answer: "",status: "",};}});},findByExpertName() {queApi.findByExpertName(this.inputValue).then((res) => {if (res.data.data == null) {alert("未查询到数据");} else {this.questionList = res.data.data;}});},},data() {return {questionList: [],question: {},inputValue: "",dialogFormVisible: false, // 控制添加的对话框是否可见form: {expertName: "",questioner: "",phone: "",plantName: "",title: "",question: "",answer: "",status: "",},formLabelWidth: "100px",rules: {expertName: [{ required: true, message: "请输入专家姓名", trigger: "blur" },],questioner: [{ required: true, message: "请输入提问人", trigger: "blur" },],phone: [{ required: true, message: "请输入电话", trigger: "blur" },//   {//     pattern: /^1[34578]\d{9}$/,//     message: "请输入正确的手机号",//     trigger: "blur",//   },],plantName: [{ required: true, message: "请输入农作物名称", trigger: "blur" },],title: [{ required: true, message: "请输入标题", trigger: "blur" }],question: [{ required: true, message: "请输入问题", trigger: "blur" }],answer: [{ required: true, message: "请输入回答", trigger: "blur" }],status: [{ required: true, message: "请输入状态", trigger: "blur" }],},};},
};
</script>