Nodejs乘法平方例子

此例实现的功能如下图所示

计算结果

代码如下

app-node.js

var http_port = 8124;
var http = require('http');
var htutil = require('./htutil');

function onRequest(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==='/mult')
	{
		require('./mult-node').get(req,res);
	}
	else
	{
		res.writeHead(404,{'Content-Type':'text/plain'});
		res.end("bad URL"+req.url);
	}
	
}

var server = http.createServer(onRequest);
server.listen(http_port);
console.log('listening to http://localhost:8124');

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();
}
//导航条
exports.navbar=function()
{
	return ["
",
			"
home
",
			"
Multiplication
",
			"
Square's
",
			"
"].join('\n');
}

exports.page=function(title, navbar, content)
{
	return ["",
			"
[title]
",
			"",
			"",
			"
{navbar}
{content}
"
			].join('\n')
			.replace("{title}", title,"g")
			.replace("[title]", title,"g")
			.replace("{navbar}", navbar, "g")
			.replace("{content}", content, "g");
}

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(),
							"
Math Wizard
")
			);
}

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;
var strT="
{a}*{b}={result}
";
strT=strT.replace("{a}", req.a);
strT=strT.replace("{b}", req.b);
strT=strT.replace("{result}", result);
var resultStr=(!isNaN(req.a)&&!isNaN(req.b))?strT:"";
res.end(
		htutil.page("Multiplication", htutil.navbar(),
					[resultStr,
					"
Enter numbers to multiply
",
					"
",
					"A: 
",
					"B: 
",
					"",
					"
"].join('\n')
					)
		);
}

square-node.js

var htutil = require('./htutil');
exports.get = function(req, res) {
res.writeHead(200, {
'Content-Type': 'text/html'
});
res.end(
htutil.page("Square", htutil.navbar(), [
(!isNaN(req.a) ?
("
{a} squared = {sq}
"
.replace("{a}", req.a)
.replace("{sq}", req.a*req.a))
: ""),
"
Enter a number to see its square
",
"
",
"A: ",
"
"
].join('\n'))
);
}

参考书籍《Node Web Development》