模块概览
dgram模块是对UDP socket的一层封装,相对net模块简单很多,下面看例子。
UPD客户端 vs UDP服务端
首先,启动UDP server,监听来自端口33333的请求。
server.js
// 例子:UDP服务端
var PORT = 33333; var HOST = '127.0.0.1'; var dgram = require('dgram'); var server = dgram.createSocket('udp4'); server.on('listening', function () { var address = server.address(); console.log('UDP Server listening on ' + address.address + ":" + address.port); }); server.on('message', function (message, remote) { console.log(remote.address + ':' + remote.port +' - ' + message); }); server.bind(PORT, HOST);
然后,创建UDP socket,向端口33333发送请求。
client.js
// 例子:UDP客户端
var PORT = 33333; var HOST = '127.0.0.1'; var dgram = require('dgram'); var message = Buffer.from('My KungFu is Good!'); var client = dgram.createSocket('udp4'); client.send(message, PORT, HOST, function(err, bytes) { if (err) throw err; console.log('UDP message sent to ' + HOST +':'+ PORT); client.close(); });
运行 server.js。
node server.js
运行 client.js。
➜ 2016.12.22-dgram git:(master) ✗ node client.js
UDP message sent to 127.0.0.1:33333
服务端打印日志如下
UDP Server listening on 127.0.0.1:33333
127.0.0.1:58940 - My KungFu is Good!
广播
通过dgram实现广播功能很简单,服务端代码如下。
var dgram = require('dgram'); var server = dgram.createSocket('udp4'); var port = 33333; server.on('message', function(message, rinfo){ console.log('server got message from: ' + rinfo.address + ':' + rinfo.port); }); server.bind(port);
接着创建客户端,向地址'255.255.255.255:33333'进行广播。
var dgram = require('dgram'); var client = dgram.createSocket('udp4'); var msg = Buffer.from('hello world'); var port = 33333; var host = '255.255.255.255'; client.bind(function(){ client.setBroadcast(true); client.send(msg, port, host, function(err){ if(err) throw err; console.log('msg has been sent'); client.close(); }); });
运行程序,最终服务端打印日志如下
➜ 2016.12.22-dgram git:(master) ✗ node broadcast-server.js
server got message from: 192.168.0.102:61010
相关链接