Express框架基本使用

用法和Flask 很相似

文档：
英文：http://expressjs.com/
中文：https://www.expressjs.com.cn/

初始化项目

# 初始化
$ npm init

# 安装
cnpm install express nodemon -S

  

 

  
1
  
2
  
3
  
4
  
5
 

项目结构

server.js
package.json
node_modules/

  

 

  
1
  
2
  
3
 

简单示例

server.js

const express = require("express");

const app = express();

app.get("/", (request, response) => { response.send("hello world!");
})

const port = process.env.PORT || 5000;

app.listen(port, () => { console.log(`Server runing on http://127.0.0.1:${port}`);
})

  

 

  
1
  
2
  
3
  
4
  
5
  
6
  
7
  
8
  
9
  
10
  
11
  
12
  
13
 

运行

$ node server.js

  

 

  
1
 

http://127.0.0.1:5000/

配置热重载

配置package.json

{
  "name": "demo",
  "version": "1.0.0",
  "description": "",
  "main": "server.js",
  "scripts": { "start": "node server.js", "dev": "nodemon server.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": { "express": "^4.17.1", "nodemon": "^2.0.2"
  }
}

  

 

  
1
  
2
  
3
  
4
  
5
  
6
  
7
  
8
  
9
  
10
  
11
  
12
  
13
  
14
  
15
  
16
 

热重载模式启动

$ npm run dev

  

 

  
1
 

数据交互

接收参数，返回json

/**
 * body 默认是undefined，需要添加解析中间件
 */
// for parsing application/json
app.use(express.json()) 
// for parsing application/x-www-form-urlencoded
app.use(express.urlencoded({ extended: true })) app.post("/json/:key", (request, response) =>{ const data = { body: request.body, params: request.params, query: request.query } response.json({ msg: 'success', code: 0, data: data})
} )


  

 

  
1
  
2
  
3
  
4
  
5
  
6
  
7
  
8
  
9
  
10
  
11
  
12
  
13
  
14
  
15
  
16
  
17
  
18
  
19
 

请求测试

POST http://127.0.0.1:5000/json/value?name=Tom&age=23
Content-Type: application/json; charset=utf-8

{ "school": "Tsinghua"
}

反回数据

{ "msg": "success", "code": 0, "data": { "body": { "school": "Tsinghua" }, "params": { "key": "value" }, "query": { "name": "Tom", "age": "23" } }
}

  

 

  
1
  
2
  
3
  
4
  
5
  
6
  
7
  
8
  
9
  
10
  
11
  
12
  
13
  
14
  
15
  
16
  
17
  
18
  
19
  
20
  
21
  
22
  
23
  
24
  
25
 

文章来源: pengshiyu.blog.csdn.net，作者：彭世瑜，版权归原作者所有，如需转载，请联系作者。

原文链接：pengshiyu.blog.csdn.net/article/details/104865850