[网络协议]golang-UDP协议

eg:

client(客户端)

package main

import (
	"bufio"
	"fmt"
	"net"
	"os"
)

//UDP client


func main() {
	socket ,err :=net.DialUDP("udp",nil,&net.UDPAddr{
		IP: net.IPv4(127,0,0,1),
		Port:40000,
	})
	if err != nil {
		fmt.Println("连接服务器失败， err:", err)
		return
	}
	var reply [1024]byte
	defer socket.Close()
	reader := bufio.NewReader(os.Stdin)
	for{
		fmt.Print("请输入内容：")
		msg,_ := reader.ReadString('\n')
		socket.Write([]byte(msg))
		//收回复的数据
		n,_,err :=  socket.ReadFromUDP(reply[:])
		if err != nil{
			fmt.Println("redv reply msg failed,err;",err)
			return
		}
		fmt.Println("收到回复信息",string(reply[:n]))
		//fmt.Println("收到回复信息",reply[:n])

	}
}

server（服务端）

package main

import (
	"fmt"
	"net"
	"strings"
)

//UDP server


func main() {
	conn ,err :=net.ListenUDP("udp",&net.UDPAddr{
		IP: net.IPv4(127,0,0,1),
		Port:40000,
	})
	if err != nil {
		fmt.Println("listen UDP failed err:", err)
		return
	}
	//不需要建立连接，直接收发数据
	var data [1024]byte
	for{
		n,addr,err := conn.ReadFromUDP(data[:])
		if err != nil {
			fmt.Println("read from UDP failed err:", err)
			return
		}
		fmt.Println(data[:n])
		reply := strings.ToUpper(string(data[:n]))
		//发送数据
		conn.WriteToUDP([]byte(reply),addr)
	}
}