Node.js_express_服务器渲染页面 ejs

服务器渲染页面 ejs

高效的 js 模版引擎

将数据提前渲染到页面上， 再将渲染好的页面返回响应给浏览器

 

提高首页加载速度

SEO 提前处理，提高加载速度

  • 下载 ejs 包

npm install ejs

无需引用，但是要配置模板资源目录

// app.set('views', '模板资源目录');

app.set('views', 'views');    // 通常文件夹 也叫 views

  • 基本使用

1. 配置模板资源目录    ( Router 没有 set 方法，所以必须在 主模块下 app.set() )

app.set('views', 'views');    // 通常文件夹 也叫 views

2. 配置要使用的模板引擎    ( Router 没有 set 方法，所以必须在 主模块下 app.set() )

app.set('views engine', 'ejs');

3. 将 后台数据 渲染到 模板资源 上

  • app.get('/ejs', (request, response)=>{
    const data = [{
        "name": '孙悟空'.
        "age": 555
    },{
            "name": '白骨精',
            "age": 18
        }];

    response.render(    'test.ejs', {data});    // .ejs 可以省略
});

4. views/test.ejs 

模板语法

1. <%        %>        其中可以写任意 js 代码

2. <%=         %>

3. <%-             %>

源码测试

  • <!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>login</title>
    </head>

    <body>

        <% console.log("哈哈"); %>
                不会显示到页面上

        <%= data[0].name %>
                输出指定数据到页面上
                不会解析标签，转义 HTML 相关源码后输出
                    安全性更高

            <%- data[1].name %>
                输出指定数据到页面上
                解析 HTML 源码
        
        
一般结合使用：
        <% for(var i=0; i<10; i++){ %>
             <%= data[i].name %>
        <% }; %>    

    </body>
</html>

凡是经过用户输入的东西，都需要进行特殊处理。

  • 完善的登录/注册实例

    

package.json

  • {
  "name": "node_express",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "connect-mongo": "^2.0.3",
    "ejs": "^2.6.1",
    "express": "^4.16.4",
    "mongoose": "^5.4.0",
    "sha1": "^1.1.1"
  }
}

public/register.html

  • <!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8"/>
        <title>用户注册</title>
        
        <link rel="stylesheet" type="text/css" href="css/index.css"/>
    </head>
    
    <body>
        <div id="outer_box" class="register">
            <h2>用户注册</h2>
            <form action="http://localhost:3000/register" method="post">
                <div class="clothes">
                    <label for="input_name">用&nbsp;户&nbsp;名</label>
                    <input id="input_name" type="text" name="user_name" placeholder="请输入用户名" />
                </div>
        
                <div class="clothes">
                    <label for="input_pwd">密&nbsp;&nbsp;&nbsp;码</label>
                    <input id="input_pwd" type="password" name="user_pwd" placeholder="请输入密码" />
                </div>
                
                <div class="clothes">
                    <label for="input_repeat_pwd">确认密码</label>
                    <input id="input_repeat_pwd" type="password" name="user_repeat_pwd" placeholder="请再次输入密码" />
                </div>
                
                <div class="clothes">
                    <label for="input_email">注册邮箱</label>
                    <input id="input_email" type="text" name="user_email" placeholder="请输入邮箱地址" />
                </div>
                
                <div class="clothes">
                    <button class="register btn" type="submit">注册</button>
                    <a class="btn" href="http://localhost:3000/login">
                        <button type="button">登录</button>
                    </a>
                </div>
            </form>
        </div>
    </body>
</html>

public/login.html

  • <!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8"/>
        <title>用户登录</title>
        
        <link rel="stylesheet" type="text/css" href="css/index.css"/>
    </head>
    
    <body>
        <div id="outer_box" class="login">
            <h2>用户登录</h2>
            <form action="http://localhost:3000/login" method="post">
                <div class="clothes">
                    <label for="input_name">用&nbsp;户&nbsp;名</label>
                    <input id="input_name" type="text" name="user_name" placeholder="请输入用户名" />
                </div>
                
                <div class="clothes">
                    <label for="input_pwd">密&nbsp;&nbsp;&nbsp;码</label>
                    <input id="input_pwd" type="password" name="user_pwd" placeholder="请输入密码" />
                </div>
                
                <div class="clothes">
                    <a class="btn" href="http://localhost:3000/register">
                        <button type="button">注册</button>
                    </a>
                    <button class="login btn" type="submit">登录</button>
                </div>
            </form>
        </div>
    </body>
</html>

public/css/index.css

  • body {
    width: 100%;
    height: 100%;
    
    color: #000;
    background: #b9c2a4;
    background-size: cover; /* 指定背景图片大小 */
}

/*************************************************/
#outer_box {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #1a45c3;
}

#outer_box.login {
    color: #9e098b;
}

#outer_box.register {
    color: #1a45c3;
}

#outer_box>h2{
    padding-bottom: 40px;
    margin-left: -50px;
}

.clothes {
    position: relative;
    width: 260px;
    display: flex;
    justify-content: space-between;
    margin: 20px 0;
    font-size: 18px;
    line-height: 32px;
}

.tips {
    position: absolute;
    top: 0;
    right: -100%;
    margin-left: -50%;
    margin-top: 2px;
    width: 252px;
    height: 32px;
    text-align: center;
    color: #f00;
}

.clothes>label{
    width: 80px;
    text-align: center;
}

.clothes>input{
    width: 170px;
    height: 32px;
}

button {
    width: 100%;
    height: 100%;
    
    font-size: 16px;
    background-color: #c4ceda;
    cursor: pointer;
}

.clothes .btn{
    width: 64px;
    height: 32px;
    margin: 0 20px;
}

.clothes button.register{
    background-color: #1a45c3;
    color: #fff;
}

.clothes button.login{
    background-color: #9e098b;
    color: #fff;
}

#outer_box>h2 {
    position: relative;
}

#server_info {
    display: block;
    width: 139px;
    height: 20px;
    border-radius: 10px;
    
    position: absolute;
    top: 0;
    right: 0;
    
    color: red;
    font-size: 14px;
    text-align: center;
    line-height: 20px;
    background-color: #cecece;
}

views/register.ejs

  • <!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8"/>
        <title>用户注册</title>
        
        <link rel="stylesheet" type="text/css" href="css/index.css"/>
    </head>
    
    <body>
        <div id="outer_box" class="register">
            <h2>用户注册</h2>
            <form action="http://localhost:3000/register" method="post">
                <div class="clothes">
                    <label for="input_name">用&nbsp;户&nbsp;名</label>
                    <input id="input_name" type="text" name="user_name" placeholder="请输入用户名" />
                    <div class="tips"><%= errInfo.name %></div>
                </div>
        
                <div class="clothes">
                    <label for="input_pwd">密&nbsp;&nbsp;&nbsp;码</label>
                    <input id="input_pwd" type="password" name="user_pwd" placeholder="请输入密码" />
                    <div class="tips"><%= errInfo.password %></div>
                </div>
                
                <div class="clothes">
                    <label for="input_repeat_pwd">确认密码</label>
                    <input id="input_repeat_pwd" type="password" name="user_repeat_pwd" placeholder="请再次输入密码" />
                    <div class="tips"><%= errInfo.repeatPassword %></div>
                </div>
                
                <div class="clothes">
                    <label for="input_email">注册邮箱</label>
                    <input id="input_email" type="text" name="user_email" placeholder="请输入邮箱地址" />
                    <div class="tips"><%= errInfo.email %></div>
                </div>
                
                <div class="clothes">
                    <button class="register btn" type="submit">注册</button>
                    <a class="btn" href="http://localhost:3000/login">
                        <button type="button">登录</button>
                    </a>
                </div>
            </form>
        </div>
    </body>
</html>

views/login.ejs

  • <!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8"/>
        <title>用户登录</title>
        
        <link rel="stylesheet" type="text/css" href="css/index.css"/>
    </head>
    
    <body>
        <div id="outer_box" class="login">
            <h2>
                用户登录
                <div id="server_info">
                    <%= data.info %>
                </div>
            </h2>
            <form action="http://localhost:3000/login" method="post">
                <div class="clothes">
                    <label for="input_name">用&nbsp;户&nbsp;名</label>
                    <input id="input_name" type="text" name="user_name" placeholder="请输入用户名" />
                </div>
                
                <div class="clothes">
                    <label for="input_pwd">密&nbsp;&nbsp;&nbsp;码</label>
                    <input id="input_pwd" type="password" name="user_pwd" placeholder="请输入密码" />
                </div>
                
                <div class="clothes">
                    <a class="btn" href="http://localhost:3000/register">
                        <button type="button">注册</button>
                    </a>
                    <button class="login btn" type="submit">登录</button>
                </div>
            </form>
        </div>
    </body>
</html>

db/connectDB.js

  • const mongoose = require('mongoose');

module.exports = new Promise((resolve, reject)=>{
    mongoose.connect('mongodb://localhost:27017/user_database', {useNewUrlParser:true})
    mongoose.connection.once('open', err=>{
        if(err){
            console.log(err);
            reject(err);
        }else{
            resolve('数据库已连接');
        };
    });
});

models/userModel.js

  • const mongoose = require('mongoose');

const Schema = mongoose.Schema;
const fieldSchema = new Schema({
    "userName": {
        "type": String,
        "unique": true,
        "required": true
    },
    "userPassword": {
        "type": String,
        "required": true
    },
    "userEmail": {
        "type": String,
        "unique": true,
        "required": true
    },
    "createTime": {
        "type": Date,
        "default": Date.now()
    }
});

module.exports = mongoose.model("user_info", fieldSchema);

routers/get/index_router.js

  • const express = require('express');
const {resolve} = require('path');

const indexRouter = new express.Router();

/************************ get ***********************/
indexRouter.get('/', (request, response)=>{
    response.sendFile(resolve(__dirname, '../../public/login.html'));
});

indexRouter.get('/login', (request, response)=>{
    response.sendFile(resolve(__dirname, '../../public/login.html'));
});

indexRouter.get('/register', (request, response)=>{
    response.sendFile(resolve(__dirname, '../../public/register.html'));
});

module.exports = indexRouter;

routers/post/form_router.js

  • const express =  require('express');
const sha1 =  require('sha1');

const promiseConnect = require('../../db/connectDB.js');
const userInfoModel = require('../../models/userModel.js');

const formRouter = new express.Router();

/************************ post ***********************/
let logged = false ;
promiseConnect.then(async result=>{
    console.log(result);
    
    formRouter.post('/register', async (request, response)=>{
        const {
            user_name:uName,
            user_pwd:uPwd,
            user_repeat_pwd:urePwd,
            user_email:uEmail,
        } = request.body;    /**** 解构赋值 ****/
        
        userInfo = {
            "userName": uName,
            "userPassword": uPwd,
            "userEmail": uEmail
        };
        
        let errInfo = {};
        
        if(urePwd !== uPwd){
            errInfo.repeatPassword = '密码两次输入不一致';
        };
        if(!(/^[a-zA-Z][a-zA-Z0-9_]{5,20}$/.test(uName))){
            errInfo.name = '用户名不合法';
        };
        if(!(/^[a-zA-Z0-9_]{6,20}$/.test(uPwd))){
            errInfo.password = '密码不合法';
        };
        if(!(/^w+([-+.]w+)*@w+([-.]w+)*.w+([-.]w+)*$/.test(uEmail))){
            errInfo.email = '邮箱不合法';
        };
    
        const fond = await userInfoModel.findOne({"userName": uName});
        if(fond){
            errInfo.name = '用户名已被注册';
        };
        
        const badEmail = await userInfoModel.findOne({"userEmail": uEmail});
        if(badEmail){
            errInfo.email = '邮箱已被注册';
        };
        
        let data = {errInfo};
        if(errInfo.repeatPassword || errInfo.name || errInfo.password || errInfo.email){
            response.render('register.ejs', data);
            return;
        }else{
            userInfo.userPassword = sha1(userInfo.userPassword);
            await userInfoModel.create(userInfo);
            data.info = "注册成功";
            response.render('login.ejs', {data});
        };
    });
    
    formRouter.post('/login',async (request, response)=>{
        logged = false;
        let uName = request.body['user_name'];
        let uPwd = request.body['user_pwd'];
        userInfo = {
            "userName": uName,
            "userPassword": uPwd
        };
        
        if(!(/^[a-zA-Z][a-zA-Z0-9_]{5,20}$/.test(uName))){
            logged = false;    // 用户名不存在
        }else if(!(/^[a-zA-Z0-9_]{6,20}$/.test(uPwd))){
            logged = false;    // 密码错误
        };
        
        const findName = await userInfoModel.findOne({"userName": uName});
        const findPwd = await userInfoModel.findOne({"userPassword": sha1(uPwd)});
        if(findName && findPwd){
            logged = true;
        };
        
        let data = {};
        logged?(data.info='登录成功'):(data.info='用户名或密码错误');
        response.render('login.ejs', {data});
    });
}).catch(err=>console.log(err));

module.exports = formRouter;

index.js

  • const express =  require('express');
const app = express();

const indexRouter = require('./routers/get/index_router.js');
const formRouter = require('./routers/post/form_router.js');

app.set('views', 'views');    // 1. 配置模板路径
app.set('view engine', 'ejs');    // 2. 配置模板引擎
/*********************** 中间件 **********************/
// 暴露路由 login.html register.html
app.use(express.static('public'));    // 默认调用 next();

// 将 用户输入的数据 挂载到 请求体 request.body  上
app.use(express.urlencoded({extended: true}));    // 默认调用 next();

app.use(indexRouter);
app.use(formRouter);

/**************** 端口号 3000, 启动服务器 ***************/
app.listen(3000, err=>console.log(err?err:'

服务器已启动: http://localhost:3000
Hunting Happy!'));

 

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原文地址：https://www.cnblogs.com/tianxiaxuange/p/10161688.html