实现思路
将data和end事件的回调函数直接放在服务器中，在data事件回调中收集所有的POST数据，当接收到所有数据，触发end事件后，其回调函数调用请求路由，并将数据传递给它，然后，请求路由再将该数据传递给请求处理程序。
实现步骤
第一步我们设置了接收数据的编码格式为UTF-8，第二步注册了“data”事件的监听器，用于收集每次接收到的新数据块，并将其赋值给postData 变量，最后第三步我们将请求路由的调用移到end事件处理程序中，以确保它只会当所有数据接收完毕后才触发，并且只触发一次。我们同时还把POST数据传递给请求路由
示例代码
index.js
var server = require("./server");
var router=require("./router");
var requestHandlers=require("./requestHandlers"); var handle = {}
handle["/"] = requestHandlers.start;
handle["/start"] = requestHandlers.start;
handle["/upload"] = requestHandlers.upload;
server.start(router.route,handle);
server.js
var http = require("http");
var url=require("url"); function start(route,handle) {
function onRequest(request, response) {
var postData="";
var pathname=url.parse(request.url).pathname;
console.log("Request for"+pathname+"received.");
request.setEncoding("utf8");
request.addListener("data", function(postDataChunk) {
postData += postDataChunk;
console.log("Received POST data chunk '"+
postDataChunk + "'.");
});
request.addListener("end", function() {
route(handle, pathname, response, postData);
});
//route(handle,pathname,response);
//response.writeHead(200, {"Content-Type": "text/plain"});
//response.write("this is a demo");
//response.end();
}
http.createServer(onRequest).listen(5656,'127.0.0.1');
console.log("Server has started. localhost:5656");
}
exports.start = start;
router.js
function route(handle,pathname,response,postData){
console.log("About to route a request for"+pathname);
if(typeof handle[pathname]=='function'){
handle[pathname](response,postData);
}
else{
console.log("no request handler found for"+pathname);
response.writeHead(404, {"Content-Type": "text/plain"});
response.write("404 Not found");
response.end();
}
}
exports.route=route; requestHandlers.js
//var querystring = require("querystring"); function start(response,postData) {
console.log("Request handler 'start' was called.");
var body = '<html>'+
