NodeJs服务端开发

Express

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Express工程环境配置

1. 安装express
   npm install express -g

2. Express项目组织生成器自动生成工程结构

   
   
   

   image.png
   
   

     /bin: 用于应用启动
     /public: 静态资源目录
     /routes：可以认为是controller（控制器）目录
     /views: jade模板目录，可以认为是view(视图)目录
     app.js 程序main文件

3. 进入工程，安装npm install依赖，然后执行npm start启动程序，在浏览器中访问对应的端口，就会看到如下结果：
   E:\nodeTest>npm start

    > [email protected] start E:\nodeTest
    > node ./bin/www  --debug
   
    addr: [object Object]
    Listening on port 80
    GET / 200 30.455 ms - 170
    GET /stylesheets/style.css 200 3.780 ms - 111
   

image.png

编写相关代码，整合Express+MySQL

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1. 新建几个目录
   在工程的根目录新建三个目录：
     util – 工具方法
     conf – 配置
     dao – 与数据库交互
   目录结构如下：

   
   
   

   image.png
2. 在conf目录中配置mySQL数据库的连接
   /**
   * Created by hzlinchanglong on 2017/1/23.
   */
   // conf/db.js
   // MySQL数据库联接配置
   module.exports = {
   mysql: {
   host: '127.0.0.1',
   user: 'root',
   password: '631020',
   database:'client', // 前面建的user表位于这个数据库中
   port: 3306
   }
   };
3. 编写SQL语句
   /**
   * Created by hzlinchanglong on 2017/1/23.
   */
   // dao/personSqlMapping.js
   // CRUD SQL语句
   var person = {
   insert:'insert into person(id, name, sex, isVip, address) values(0,?,?,?,?)',
   update:'update person set name=?, sex=?, isVip=?, address=? where id=?',
   delete: 'delete from person where id=?',
   queryById: 'select * from person where id=?',
   queryAll: 'select * from person'
   };

module.exports = person;

4. 在/routes/users.js中添加路由
   var express = require('express');
   var router = express.Router();
   var userDao = require('../dao/userDao');

    /* GET users listing. */
    router.get('/', function(req, res, next) {
      res.render('updateUser');
    });
    // 增加用户
    router.get('/addUser', function(req, res, next) {
      userDao.add(req, res, next);
    });
   
    router.get('/queryAll', function(req, res, next) {
      userDao.queryAll(req, res, next);
    });
   
    router.get('/query', function(req, res, next) {
      userDao.queryById(req, res, next);
    });
   
    router.get('/deleteUser', function(req, res, next) {
      userDao.delete(req, res, next);
    });
   
    router.post('/updateUser', function(req, res, next) {
      userDao.update(req, res, next);
    });
   
    module.exports = router;
   

5. 在/dao/userDao.js中实现add、delete、update、queryById、queryAll方法
   /**
   * Created by hzlinchanglong on 2017/1/23.
   */
   // dao/userDao.js
   // 实现与MySQL交互
   var mysql = require('mysql');
   var $conf = require('../conf/db');
   var $util = require('../util/util');
   var $sql = require('./personSqlMapping');

    // 使用连接池，提升性能
    var pool  = mysql.createPool($util.extend({}, $conf.mysql));
   
    // 向前台返回JSON方法的简单封装
    var jsonWrite = function (res, ret) {
        if(typeof ret === 'undefined') {
            res.json({
                code:'1',
                msg: '操作失败'
            });
        } else {
            res.json(ret);
        }
    };
   
    module.exports = {
        add: function (req, res, next) {
            pool.getConnection(function(err, connection) {
                // 获取前台页面传过来的参数
                var param = req.query || req.params;
                // 建立连接，向表中插入值
                connection.query($sql.insert, [param.id, param.name, param.sex,         param.isVip, param.address], function(err, result) {
                    // 以json形式，把操作结果返回给前台页面
                    jsonWrite(res, result);
                    // 释放连接
                    connection.release();
                });
            });
        },
        delete: function (req, res, next) {
            // delete by Id
            pool.getConnection(function(err, connection) {
                var id = +req.query.id;
                connection.query($sql.delete, id, function(err, result) {
                    if(result.affectedRows > 0) {
                        result = {
                            code: 200,
                            msg:'删除成功'
                        };
                    } else {
                        result = void 0;
                    }
                    jsonWrite(res, result);
                    connection.release();
                });
            });
        },
        update: function (req, res, next) {
            // update by id
            // 为了简单，要求同时传name和age两个参数
            var param = req.body;
            if(param.name == null || param.sex == null || param.id == null || param.address == null || param.isVip == null) {
                return;
            }
   
            pool.getConnection(function(err, connection) {
                connection.query($sql.update, [param.name, param.sex, param.isVip, param.address, +param.id], function(err, result) {
                    // 使用页面进行跳转提示
                    console.log('err:' + err);
                    if(result.affectedRows > 0) {
                        res.render('suc', {
                            result: result
                        }); // 第二个参数可以直接在jade中使用
                    } else {
                        res.render('fail',  {
                            result: result
                        });
                    }
                    connection.release();
                });
            });
   
        },
        queryById: function(req, res, next) {
            var id = req.query.id;
            pool.getConnection(function(err, connection) {
                connection.query($sql.queryById, id, function(err, result) {
                    jsonWrite(res, result);
                    connection.release();
                })
            })
        },
        queryAll: function (req, res, next) {
            pool.getConnection(function(err, connection) {
                connection.query($sql.queryAll, function(err, result) {
                    jsonWrite(res, result);
                    connection.release();
                });
            });
        }
    };
   

6. 在/views目录新建三个jade文件
   updateUser.jade
   //
   Created by hzlinchanglong on 2017/1/24.
   extends layout
   block content
   h1 更新用户资料
   form(method='post', action='/users/updateUser')
   div.form-row
   label
   span ID:
   input(type='text',name='id')
   div.form-row
   label
   span name:
   input(type='text',name='name')
   div.form-row
   label
   span sex:
   input(type='text',name='sex')
   div.form-row
   label
   span isVip:
   input(type='text',name='isVip')
   div.form-row
   label
   span address:
   input(type='text',name='address')
   div.form-row
   input(type='submit')
   fail.jade
   //
   Created by hzlinchanglong on 2017/1/24.
   block content
   h1 操作失败！
   pre #{JSON.stringify(result)}
   suc.jade
   //
   Created by hzlinchanglong on 2017/1/24.
   block content
   h1 操作成功！
   pre #{JSON.stringify(result)}
   在浏览器中运行的结果如下：

image.png