服务器端

package main
import (
	"fmt"
	"net"
	"strings"
)
func  HandleConnect( conn net.Conn)  {
		defer conn.Close()
		addr:=conn.RemoteAddr()
		fmt.Println(addr,"客户端成功连接")
		buf:=make([]byte,4096)
		for {
			n,err:=conn.Read(buf)
			if "exit\n" == string(buf[:n]) ||  "exit\r\n" == string(buf[:n]){
				fmt.Println("客户端关闭连接")
				return
			}
			if n ==0 {
				fmt.Println("Client is close")
				return
			}
			if err != nil {
				fmt.Println("conn Read err",err)
				return
			}
			fmt.Println("服务器读到客户端数据:",string(buf[:n]))
			conn.Write([]byte(strings.ToUpper(string(buf[:n]))))
		}
}
func main(){
	listener,err:= net.Listen("tcp","127.0.0.1:9001")
	if err != nil {
		fmt.Println("net.listen is error")
		return
	}
	defer listener.Close()
	fmt.Println("服务器等待客户端连接...")
	for {
		conn,err:= listener.Accept()
		if err != nil {
			fmt.Println("accept is error") 
			return
		}
		go HandleConnect(conn)
	}
}

客户端

package main

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

func main(){
	conn,err:=net.Dial("tcp","127.0.0.1:9001")
	if err != nil {
		fmt.Println("connect server is error")
		return
	}
	defer conn.Close()

	go func(){
		str:=make([]byte,4096)
		for {
			n,err:=os.Stdin.Read(str)
			if n ==0 {
				fmt.Println("server is close")
				return
			}
			if err != nil {
				fmt.Println("os.Stdin is error")
				continue
			}
			conn.Write(str[:n])
		}
	}()
	//读取服务器
	buf:=make([]byte,4096)
	for {
		n,err:=conn.Read(buf)
		if n == 0 {
			fmt.Println("服务端关闭连接了...")
			return
		}
		if "exit\n" == string(buf[:n]) || "exit\r\n" == string(buf[:n]) {
			fmt.Println("客户端关闭连接")
			return
		}
		if err != nil {
			fmt.Println("os.buf is error")
			return
		}
		fmt.Println("客户端读到服务端数据：", string(buf[:n]))
	}
}