# node-express

**Repository Path**: JohnCheng/node-express

## Basic Information

- **Project Name**: node-express
- **Description**: node搭建express用于api调用
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2024-03-23
- **Last Updated**: 2024-03-24

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

## Express

### 1.初始化项目

```javascript
pnpm init
```

### 2.Express 介绍和安装

Express 是基于 Node.js 平台，快速、开放、极简的 Web 开发框架。

```javascript
pnpm install express

```

#### 2.1 配置以及启动 http 服务

```javascript
const express = require("express");
const app = express();
const port = 3000;

app.get("/", (req, res) => {
  res.send("Hello World!");
});

app.listen(port, () => {
  console.log(`Example app listening on port ${port}`);
});
```

#### 2.2 启动服务

```javascript
node app.js
```

#### 2.3 访问服务

```javascript
http://localhost: 3000;
```

### 3.安装和访问 mysql

#### 3.1 安装 mysql

```javascript
pnpm install mysql
```

#### 3.2 配置链接信息

```javascript
var mysql = require("mysql");
var connection = mysql.createConnection({
  host: "localhost",
  user: "root",
  password: "123456",
  database: "zx_rise_booksystem",
});

connection.connect();
connection.query("", function (err, rows, fields) {
  if (err) {
    console.log("The solution is:", rows[0]["solution"]);
  } else {
    console.log("success", rows[0]["solution"]);
  }
});
connection.end();
```

#### 3.4 访问 mysql

```javascript
http://localhost: 3000;

// 控制台信息
Example app listening on port 3000
success 2
```

#### 3.5 抽取配置文件

1、创建 config.js 文件

```javascript
const configs = {
  mysql: {
    host: "127.0.0.1",
    user: "root",
    password: "123456",
    database: "zx_rise_booksystem",
  },
};

module.exports = configs;
```

2、app.js 导入并使用配置

```javascript
const configs = require("./config");

var mysql = require("mysql");
var connection = mysql.createConnection(configs.mysql);

connection.connect();
connection.query("select 1 + 1 as solution", function (err, rows, fields) {
  if (err) throw err;

  console.log("The solution is:", rows[0]["solution"]);
});
connection.end();
```

### 4.crud 接口的实现

```javascript
/**
 * get请求 返回json格式list数据
 */
app.get("/get", (req, res) => {
  var sql = `SELECT * FROM Book`;
  if (req.query.BookName) {
    sql = `SELECT * FROM book Where BookName Like'%${req.query.BookName}%'`;
  }
  connection.query(sql, (err, rows) => {
    if (!err) {
      res.send(rows);
    } else {
      res.send(err);
    }
  });
});

/**
 * post请求 添加
 */
app.post("/add", (req, res) => {
  let sql = `INSERT into book(BookName,Author,TypeName,Remarks) VALUES('${req.body.BookName}','${req.body.Author}','${req.body.TypeName}','${req.body.Remarks}')`;
  connection.query(sql, (err, rows) => {
    if (!err) {
      res.send("操作成功！");
    } else {
      res.send(err);
    }
  });
});

/**
 * post请求 编辑
 */
app.post("/edit", (req, res) => {
  let sql = `UPDATE book SET BookName='${req.body.BookName}', Author='${req.body.Author}', TypeName='${req.body.TypeName}', Remarks='${req.body.Remarks}' where id=${req.body.Id}`;
  connection.query(sql, (err, rows) => {
    if (!err) {
      res.send("操作成功！");
    } else {
      res.send(err);
    }
  });
});

/**
 * get请求 删除
 */
app.get("/del", (req, res) => {
  let sql = `DELETE FROM book where Id=${req.body.Id};`;
  connection.query(sql, (err, rows) => {
    if (!err) {
      res.send("操作成功！");
    } else {
      res.send(err);
    }
  });
});
```

### 5.接口参数的解析（补充）

```javascript
// 安装依赖
pnpm install body-parser

// 引入body-parse
var bodyParser = require("body-parser");
// 解析应用程序 x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }));
// 解析application/json
app.use(bodyParser.json());
```

### 6.sql 文件

```sql
当前文件夹下： zx_rise_booksystem.sql
```