Open main.js in the src directory , this file is the entry file of the project, so import it here, other components can be used, no need to import.

import Vue from 'vue'

//新添
import ElementUI from 'element-ui' 

//新增
import 'element-ui/lib/theme-chalk/index.css'

//新增
Vue.use(ElementUI) 
。。。

2 Create the login page

2.1 Create the login component

1) Create a new views directory, right-click on the directory, select New vue (simple module) to create a Login

<template>
</template>

<script>
</script>

<style>
</style>

2) In the element-ui component, find a component similar to the login page in the form component, copy the code to the newly created Login component, and modify it to the login page you need. The page contains: account, password, submit button

<template>
    <div>
        <el-form >
            <el-form-item label="账户" >
              <el-input type="password" v-model="userName" autocomplete="off"></el-input>
            </el-form-item>
            <el-form-item label="密码" >
              <el-input type="password" v-model="passWord" autocomplete="off"></el-input>
            </el-form-item>
            <el-form-item>
              <el-button type="primary" @click="submitForm('ruleForm')">提交</el-button>
            </el-form-item>
         </el-form>
    </div>
</template>

<script>
  export default {
    name: 'Login',
    data: function() {
      return {
         userName: null,
         passWord: null,
      }
    },
    methods: {
      submitForm: function() {
          console.log("fdfdd");
      }
    }
  }
</script>

<style>
</style>

2.2 Import css (css.txt)

Import according to the instructions in css.txt to control styles and add styles

css style:

<style>
.login-wrap {
box-sizing: border-box;
width: 100%;
height: 100%;
padding-top: 10%;
background-image: url(data:image/svg+xml;base64,<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<svg width="1361px" height="609px" viewBox="0 0 1361 609" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <!-- Generator: Sketch 46.2 (44496) - http://www.bohemiancoding.com/sketch -->
    <title>Group 21</title>
    <desc>Created with Sketch.</desc>
    <defs></defs>
    <g id="Ant-Design-Pro-3.0" stroke="none" stroke-width="1" fill="none" fill-rule="evenodd">
        <g id="账户密码登录-校验" transform="translate(-79.000000, -82.000000)">
            <g id="Group-21" transform="translate(77.000000, 73.000000)">
                <g id="Group-18" opacity="0.8" transform="translate(74.901416, 569.699158) rotate(-7.000000) translate(-74.901416, -569.699158) translate(4.901416, 525.199158)">
                    <ellipse id="Oval-11" fill="#CFDAE6" opacity="0.25" cx="63.5748792" cy="32.468367" rx="21.7830479" ry="21.766008"></ellipse>
                    <ellipse id="Oval-3" fill="#CFDAE6" opacity="0.599999964" cx="5.98746479" cy="13.8668601" rx="5.2173913" ry="5.21330997"></ellipse>
                    <path d="M38.1354514,88.3520215 C43.8984227,88.3520215 48.570234,83.6838647 48.570234,77.9254015 C48.570234,72.1669383 43.8984227,67.4987816 38.1354514,67.4987816 C32.3724801,67.4987816 27.7006688,72.1669383 27.7006688,77.9254015 C27.7006688,83.6838647 32.3724801,88.3520215 38.1354514,88.3520215 Z" id="Oval-3-Copy" fill="#CFDAE6" opacity="0.45"></path>
                    <path d="M64.2775582,33.1704963 L119.185836,16.5654915" id="Path-12" stroke="#CFDAE6" stroke-width="1.73913043" stroke-linecap="round" stroke-linejoin="round"></path>
                    <path d="M42.1431708,26.5002681 L7.71190162,14.5640702" id="Path-16" stroke="#E0B4B7" stroke-width="0.702678964" opacity="0.7" stroke-linecap="round" stroke-linejoin="round" stroke-dasharray="1.405357899873153,2.108036953469981"></path>
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                    <g id="Group-17" transform="translate(126.850922, 13.543654) rotate(30.000000) translate(-126.850922, -13.543654) translate(117.285705, 4.381889)" fill="#CFDAE6">
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                    </g>
                </g>
                <g id="Group-14" transform="translate(216.294700, 123.725600) rotate(-5.000000) translate(-216.294700, -123.725600) translate(106.294700, 35.225600)">
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                    <path d="M29.1176471,39.9329268 L29.1176471,18.347561 C23.1616351,18.347561 18.3333333,23.1796097 18.3333333,29.1402439 C18.3333333,35.1008781 23.1616351,39.9329268 29.1176471,39.9329268 Z" id="Oval-2" fill="#BACAD9"></path>
                    <g id="Group-9" opacity="0.45" transform="translate(172.000000, 131.000000)" fill="#E6A1A6">
                        <ellipse id="Oval-2-Copy-2" cx="7.01960784" cy="7.14634146" rx="6.47058824" ry="6.47560976"></ellipse>
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                    </g>
                    <ellipse id="Oval-10" fill="#CFDAE6" cx="218.382353" cy="138.685976" rx="1.61764706" ry="1.61890244"></ellipse>
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                    <ellipse id="Oval-10-Copy" fill="#E0B4B7" opacity="0.35" cx="180.098039" cy="102.530488" rx="2.15686275" ry="2.15853659"></ellipse>
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                </g>
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                    </g>
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                </g>
                <g id="Group-19" opacity="0.33" transform="translate(1282.537219, 446.502867) rotate(-10.000000) translate(-1282.537219, -446.502867) translate(1142.537219, 327.502867)">
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                        <circle id="Oval-4" opacity="0.45" cx="11.6666667" cy="11.6666667" r="11.6666667"></circle>
                        <path d="M23.3333333,23.3333333 C23.3333333,16.8900113 18.1099887,11.6666667 11.6666667,11.6666667 C5.22334459,11.6666667 0,16.8900113 0,23.3333333 L23.3333333,23.3333333 Z" id="Oval-4" transform="translate(11.666667, 17.500000) scale(-1, -1) translate(-11.666667, -17.500000) "></path>
                    </g>
                    <circle id="Oval-5-Copy-6" fill="#CFDAE6" cx="201.833333" cy="87.5" r="5.83333333"></circle>
                    <path d="M143.5,88.8126685 L155.070501,17.6038544" id="Path-17" stroke="#BACAD9" stroke-width="1.16666667"></path>
                    <path d="M17.5,37.3333333 L127.466252,97.6449735" id="Path-18" stroke="#BACAD9" stroke-width="1.16666667"></path>
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                    <circle id="Oval-5" fill="#C1D1E0" cx="156.916667" cy="8.75" r="8.75"></circle>
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                    <circle id="Oval-5-Copy-2" fill-opacity="0.6" fill="#D1DEED" cx="8.75" cy="33.25" r="8.75"></circle>
                    <circle id="Oval-5-Copy-4" fill-opacity="0.6" fill="#D1DEED" cx="243.833333" cy="30.3333333" r="5.83333333"></circle>
                    <circle id="Oval-5-Copy-5" fill="#E0B4B7" cx="175.583333" cy="232.75" r="5.25"></circle>
                </g>
            </g>
        </g>
    </g>
</svg>);
/* background-color: #112346; */
background-repeat: no-repeat;
background-position: center right;
background-size: 100%;
}
.login-container {
border-radius: 10px;
margin: 0px auto;
width: 350px;
padding: 30px 35px 15px 35px;
background: #fff;
border: 1px solid #eaeaea;
text-align: left;
box-shadow: 0 0 20px 2px rgba(0, 0, 0, 0.1);
}
.title {
margin: 0px auto 40px auto;
text-align: center;
color: #505458;
}
.remember {
margin: 0px 0px 35px 0px;
}
.code-box {
text-align: right;
}
.codeimg {
height: 40px;
}
.title {
text-align: center;

}
</style>

Base64 encoding:
Based on 64 printable characters to represent binary data, it is used to transmit 8Bit byte codes, which can be used to transmit long identification information in the HTTP environment. Encoding with Base64 is unreadable and needs to be decoded before it can be read.

2.3 Configure routing

router/index.js

import Vue from 'vue'
import Router from 'vue-router'
import HelloWorld from '@/components/HelloWorld'

//首先导入组件
import Login from '@/views/Login'

Vue.use(Router)

export default new Router({
  routes: [
    {
      //配置路由，根路径访问Login组件
      path: '/',
      name: 'Login',
      component: Login
    }
  ]
})

2.4 Adjust the submit button to 100% width in the Login component

<el-button type="primary" @click="submitForm('ruleForm')" style="width:100%">提交</el-button>

2.5 Running effect

In the project directory, run the following command to start the service:

npm run dev

Interface effect:

3. Background interaction

3.1 Introducing axios

Axios is a lightweight version of ajax advocated by vue2. It is a promise-based HTTP library. It creates XMLHttpRequests from the browser and works great with Vue.
Vue.js has the famous family bucket series: vue-router, vuex, vue-resource, plus the build tool vue-cli, which is the core component of a complete vue project. Among them, vue-resource is a plug-in of Vue.js. It can initiate requests and process responses through XMLHttpRequest or JSONP, but after vue is updated to 2.0, the author announced that vue-resource will no longer be updated, but the recommended axios

3.2 axios/qs/vue-axios installation and use

Note:
qs.js is a js library for url parameter conversion. There are two usages:

var obj = qs.parse('a=b&c=d');  //将URL解析成对象的形式：{a:'b',c:'d'}
var str = qs.stringify(obj);    //将对象 序列化成URL的形式，以&进行拼接：a=b&c=d'

vue-axios is a plugin that extends on the basis of axios. It extends properties such as $http on the Vue.prototype prototype, which makes it easier to use axios

3.2.1 Install axios

npm install axios -S

You can see the new library installed under dependencies in package.json

2) Import axios in the Login component

  import axios from 'axios'
  export default {
  ......

3.2.2 Send get request:

Add the code that sends the get request to the listener function of the submit button:

//请求url，需要保证服务可用
let url = 'http://localhost:8080/webserver/userMsg/userAction!login.action';
//注意数据是保存到json对象的params属性
axios.get(url, {
  params: {
    userNo: this.userNo,
    userPwd: this.userPwd
  }
}).then(function(response) {
  console.log(response);
}).catch(function(error) {
  console.log(error);
});

Please pay attention to the error message on the following figure, the request has a cross-domain error problem:

Cross-domain request problem:
Because we use the method of separating the front-end and back-end for development, the front-end and back-end are on different servers. Based on security considerations, the browser has a same-origin policy, so there is a cross-domain problem.
Same-origin policy is a security feature of browsers. Client-side scripts from different origins cannot read or write resources from each other without explicit authorization. The Same Origin Policy is the cornerstone of browser security.

4)
Handling of cross-domain problems To handle cross-domain problems in the filter, the key code:

// Access-Control-Allow-Origin就是我们需要设置的域名
// Access-Control-Allow-Headers跨域允许包含的头。
// Access-Control-Allow-Methods是允许的请求方式
httpResponse.setHeader("Access-Control-Allow-Origin", "*");// *,任何域名
httpResponse.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
httpResponse.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, DELETE");
filterChain.doFilter(servletRequest, servletResponse);

CorsFilter is provided in the courseware materials and configured in web.xml to intercept all requests, which can solve cross-domain problems. Note: Please configure before struts central controller

3.2.3 Send post request:

//注意数据是直接保存到json对象
axios.post(url, {
    userNo: 'admin',
    userPwd: '123'
}).then(function(response) {
    console.log(response);
}).catch(function(error) {
    console.log(error);
});

The input test account and password are correct, and the response obtained by using get to send the request is "password is correct", but the response of the request sent by post method is "password is incorrect"!

Reason analysis :

By observing the console, it can be found that when the post sends a request, the request parameters are sent in json format through the request payload, and the struts does not handle the parameters passed in this way (at least the struts version we use), so pass it to The server parameters were not parsed efficiently.

Problem handling:
The first way: Implement the request payload parameter parsing by coding on the server side. Add a method to BaseAction that gets json data from the request payload and converts it to the specified class.

public Object getRequestBody(Class clazz) {   

        BufferedReader br;
        HttpServletRequest request = ServletActionContext.getRequest();

        try {
            br = request.getReader();
            String str, aStr = "";
            while((str = br.readLine()) != null){
                aStr += str;
            }

            System.out.println(aStr);
            Object obj = JSONObject.parseObject(aStr, clazz);

            return obj;
        } catch (IOException e) {
           throw new RuntimeException("获取请求参数异常: " + e);
        }
    }

Call this method when getting parameters to get

User user = (User)this.getRequestBody(User.class);

The second way: use the qs.js library to convert {a:'b',c:'d'} into 'a=b&c=d'.
1) Install qs and vue-axios

npm install qs -S

npm install vue-axios -S

After the installation is successful, you will see the new library installed in "dependencies" in package.json.

Use qs to convert the json object when submitting the request

//注意数据是直接保存到json对象
let params = {
  userNo: 'admin',
  userPwd: '123'
};

//参数格式转换
let paramStr = qs.stringify(params);
console.log(paramStr);

//提交时使用转换之后的参数
axios.post(url, paramStr).then(function(response) {
  console.log(response);
}).catch(function(error) {
  console.log(error);
});

Observe the output in the console, the json format has been converted to & concatenated format. See if the returned result is the expected value.

3.2.4 Simplify the use of axios

To simplify the use of axios, you can also use axios global configuration and interceptors

1) Install vue-axios

npm install vue-axios -S

2) Test the api directory provided with the courseware to the src root path

Now you can delete the import axios and qs statements in the Login component. For the configuration of action.js and http.js, see the comments in the code.

3) Modify the configuration in action to your own background service configuration

export default {
	'SERVER': 'http://localhost:8080/webserver', //服务器
	'SYSTEM_USER_DOLOGIN': '/userMsg/userAction!login.action', //登陆
	'SYSTEM_USER_DOREG': '/userAction.action', //注册
  //获取完整的请求地址
	'getFullPath': k => { //获得请求的完整地址，用于mockjs测试时使用
		return this.SERVER + this[k];
	}
}

4) Configure main.js

import Vue from 'vue'

//vue项目对axios的全局配置（增加配置）
import axios from '@/api/http'
import VueAxios from 'vue-axios'
Vue.use(VueAxios,axios)
......

5) There is no need to manually process the conversion when submitting, and the global configuration is converted.

//修改url的获取方式，url已经配置在了action.js中，这里只要指定action路径
//服务地址和服务上下文已经在http.js中设置了axios.defaults.baseURL，
//axios会根据配置自动获取。
let url = this.axios.urls.SYSTEM_USER_DOLOGIN;
this.axios.post(url, params).then(resp => {
  console.log(resp);
}).catch(resp => {});

6) A post request occurs, test

Use vue-cli to create login page & background interaction

1. Build the project

1.1 Create a project with vue-cli

1.2 Install element-ui via npm

1.3 Import components