从零开始学习Node.js系列教程四：多页面实现的数学运算示例

时间：2021-05-25

本文实例讲述了Node.js多页面实现的数学运算。分享给大家供大家参考，具体如下：

app-node.js

var http_port = 3000;var http = require('http');var htutil = require('./htutil');var server = http.createServer(function(req, res){ htutil.loadParams(req, res, undefined); if (req.requrl.pathname === '/'){ require('./home-node').get(req, res); }else if (req.requrl.pathname === '/square'){ require('./square-node').get(req, res); }else if (req.requrl.pathname === '/factorial'){ require('./factorial-node').get(req, res); }else if (req.requrl.pathname === '/fibonacci'){ require('./fibo-node').get(req, res); }else if (req.requrl.pathname === '/mult'){ require('./mult-node').get(req, res); }else{ res.writeHead(404, {'Content-Type': 'text/plain'}); res.end("bad URL" + req.url); }});server.listen(http_port);console.log('listening to http://localhost:3000');

htutil.js

var url = require('url');exports.loadParams = function(req, res, next){ req.requrl = url.parse(req.url, true); req.a = (req.requrl.query.a && !isNaN(req.requrl.query.a)) ? new Number(req.requrl.query.a) : NaN; req.b = (req.requrl.query.b && !isNaN(req.requrl.query.b)) ? new Number(req.requrl.query.b) : NaN; if(next) next();}exports.navbar = function(){ return ["<div class='navbar'>", "<p><a href='/'>home</a></p>", "<p><a href='/mult'>Multiplication</a></p>", "<p><a href='/square'>Square</a></p>", "<p><a href='/factorial'>Factorial</a></p>", "<p><a href='/fibonacci'>Fibonacci</a></p>", "</div>"].join('\n');}exports.page = function(title, navbar, content){ return ["<html><head><title>{title}</title></head>", "<body><h1>{title}</h1>", "<table><tr>", "<td>{navbar}</td><td>{content}</td>", "</tr></table></body></html>" ].join('\n') .replace(new RegExp("{title}", "gm"), title) .replace("{navbar}", navbar) .replace("{content}", content);}

home-node.js

var htutil = require('./htutil');exports.get = function(req, res){ res.writeHead(200, {'Content-Type': 'text/html'}); res.end(htutil.page("Math Wizard", htutil.navbar(), "<p>Math Wizard</p>"));}

square-node.js

var htutil = require('./htutil');exports.get = function(req, res){ res.writeHead(200, {'Content-Type': 'text/html'}); var result = req.a * req.a; res.end( htutil.page("Square", htutil.navbar(), [ (!isNaN(req.a) ? ("<p class='result'>{a} squared = {sq}</p>" .replace("{a}", req.a) .replace("{sq}", req.a * req.a)) : ""), "<p>Enter numbers to see its square</p>", "<form name='square' action='/square' method='get'>", "A: <input type='text' name='a' /><br/>", "<input type='submit' value='Submit' />", "</form>" ].join('\n')) );}

factorial-node.js

var htutil = require('./htutil');var math = require('./math');exports.get = function(req, res){ res.writeHead(200, {'Content-Type': 'text/html'}); res.end( htutil.page("Factorial", htutil.navbar(), [ (!isNaN(req.a) ? ("<p class='result'>{a} factorial = {fact}</p>" .replace("{a}", req.a) .replace("{fact}", math.factorial(Math.floor(req.a)))) : ""), "<p>Enter numbers to see its factorial</p>", "<form name='factorial' action='/factorial' method='get'>", "A: <input type='text' name='a' /><br/>", "<input type='submit' value='Submit' />", "</form>" ].join('\n')) );}

mult-node.js

var htutil = require('./htutil');exports.get = function(req, res){ res.writeHead(200, {'Content-Type': 'text/html'}); var result = req.a * req.b; res.end( htutil.page("Multiplication", htutil.navbar(), [ (!isNaN(req.a) && !isNaN(req.b) ? ("<p class='result'>{a} * {b} = {result}</p>" .replace("{a}", req.a) .replace("{b}", req.b) .replace("{result}", req.a * req.b)) : ""), "<p>Enter numbers to mutiply</p>", "<form name='mult' action='/mult' method='get'>", "A: <input type='text' name='a' /><br/>", "B: <input type='text' name='b' /><br/>", "<input type='submit' value='Submit' />", "</form>" ].join('\n')) );}

fibo-node.js

var htutil = require('./htutil');var math = require('./math');exports.get = function(req, res){ res.writeHead(200, {'Content-Type': 'text/html'}); res.end( htutil.page("Fibonacci", htutil.navbar(), [ (!isNaN(req.a) ? ("<p class='result'>{a} fibonacci = {fibo}</p>" .replace("{a}", Math.floor(req.a)) .replace("{fibo}", math.fibonacci(Math.floor(req.a)))) : ""), "<p>Enter numbers to see its fibonacci</p>", "<form name='fibonacci' action='/fibonacci' method='get'>", "A: <input type='text' name='a' /><br/>", "<input type='submit' value='Submit' />", "</form>" ].join('\n')) );}

fibo2-node.js

var htutil = require('./htutil');var math = require('./math');function sendResult(req, res, a, fiboval){ res.writeHead(200, {'Content-Type': 'text/html'}); res.end( htutil.page("Fibonacci", htutil.navbar(), [ (!isNaN(fiboval) ? ("<p class='result'>{a} fibonacci = {fibo}</p>" .replace("{a}", a) .replace("{fibo}", fiboval)) : ""), "<p>Enter numbers to see its fibonacci</p>", "<form name='fibonacci' action='/fibonacci' method='get'>", "A: <input type='text' name='a' /><br/>", "<input type='submit' value='Submit' />", "</form>" ].join('\n')) );}exports.get = function(req, res){ if (!isNaN(req.a)){ math.fibonacciAsync(Math.floor(req.a), function(val){ sendResult(req, res, Math.floor(req.a) ,val); }); }else { sendResult(req, res, NaN, NaN); }}

math.js

var factorial = exports.factorial = function(n){ if (n == 0) return 1; else return n * factorial(n-1);}var fibonacci = exports.fibonacci = function(n){ if (n === 1) return 1; else if (n === 2) return 1; else return fibonacci(n-1) + fibonacci(n-2);}var fibonacciAsync = exports.fibonacciAsync = function(n, done){ if (n ==1 || n == 2) done(1); else { process.nextTick(function(){ fibonacciAsync(n-1, function(val1){ process.nextTick(function(){ fibonacciAsync(n-2, function(val2){ done(val1 + val2); }); }) }); }); }}

希望本文所述对大家nodejs程序设计有所帮助。

声明：本页内容来源网络，仅供用户参考；我单位不保证亦不表示资料全面及准确无误，也不保证亦不表示这些资料为最新信息，如因任何原因，本网内容或者用户因倚赖本网内容造成任何损失或损害，我单位将不会负任何法律责任。如涉及版权问题，请提交至online#300.cn邮箱联系删除。

相关文章