node.js+express制作网页计算器

2020-06-17 07:39:51易采站长站整理

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;