node.js+express制作网页计算器

环境:

主机:WIN10

express安装:

1.安装express-generator

输入命令:

npm install -g express-generator

2.安装express

输入命令:

npm install -g express

3.验证是否安装成功

输入命令:express -V

查看帮助:express --help

建立工程:

express -e calculator

cd calculator && npm install

运行默认网页:

输入命令:npm start或者node ./bin/www

端口配置在/bin/www中。

可以执行加法运算。

源代码:

view/index.ejs:增加输入框

<!DOCTYPE html> 
<html> 
 <head> 
  <title><%= title %></title> 
  <link rel='stylesheet' href='/stylesheets/style.css' /> 
 </head> 
 <body> 
    <form method="post"> 
      <p>计算器</p> 
    <input type="text" name="num1" value=<%= numa %> /><br /> 
    <input type="text" name="num2" value=<%= numb %> /><br /> 
    <input type="submit" value="计算" /> 
    <p>结果:<%= sum %></p> 
    </form> 
 </body> 
</html> 

routes/index.js:对提交的数据进行计算并推送结果

var express = require('express'); 
var router = express.Router(); 
 
/* GET home page. */ 
router.get('/', function(req, res, next) { 
 res.render('index', {  
  title: '计算器V1.0 by jdh', 
  numa: 0, 
    numb: 0, 
    sum: 0 
 }); 
}); 
 
router.post('/', function (req, res) { 
  console.log("接收:", req.body.num1, req.body.num2); 
  var sum = parseFloat(req.body.num1) + parseFloat(req.body.num2); 
  console.log('sum = ',sum); 
   
  res.render('index', {  
  title: '计算器V1.0 by jdh', 
// numa: req.body.num1, 
//   numb: req.body.num2 
    numa: req.body.num1, 
    numb: req.body.num2, 
    sum: sum 
 }); 
}); 
   
module.exports = router;