golang入门案例之SOCKET

Posted 2020-10-21 打败大魔王

//服务端代码
package main
import (
	"fmt"
	"net"
	"log"
	"os"
	"encoding/binary"
)


func main() {


	//建立socket，监听端口
	netListen, err := net.Listen("tcp", "localhost:8090")
	CheckError(err)
	defer netListen.Close()

	Log("Waiting for clients")
	for {
		conn, err := netListen.Accept()
		if err != nil {
			continue
		}

		Log(conn.RemoteAddr().String(), " tcp connect success")
		handleConnection(conn)
	}
}
//处理连接
func handleConnection(conn net.Conn) {

	//buffer := make([]byte, 2048)

	for {
		var pi float64
		var a uint16

		err := binary.Read(conn, binary.LittleEndian, &pi)//读取浮点数
		err = binary.Read(conn, binary.LittleEndian, &a)//读取整数
		CheckError(err)

		if err != nil {
			Log(conn.RemoteAddr().String(), " connection error: ", err)
			return
		}


		Log(conn.RemoteAddr().String(), "receive data string:\n", (pi), ", uint16 a= " , a)

	}
}
func Log(v ...interface{}) {
	log.Println(v...)
}

func CheckError(err error) {
	if err != nil {
		fmt.Fprintf(os.Stderr, "Fatal error: %s", err.Error())
		os.Exit(1)
	}
}

客户端:

package main

import (
   "fmt"
   "net"
   "os"
   "bytes"
   "encoding/binary"
)


var x float32 = 1.2 //1.2

func init()  { //1.3

   fmt.Printf("p1 package, x:%f\n", x) //1.4
}

func Donothing() {

   fmt.Println("do nothing.\n")
}


func sender(conn net.Conn) {

   var pi float64 = 3.141592653589793
   buf := new(bytes.Buffer)
   err := binary.Write(buf, binary.LittleEndian, pi)//向buf中写入浮点数
   if err != nil {
      fmt.Println("binary.Write failed:", err)
   }
   // 这里可以继续往buf里写, 都存在buf里
   err = binary.Write(buf, binary.LittleEndian, uint16(12345))//向buf中写入整数
   if err != nil {
      fmt.Println("binary.Write failed:", err)
   }
   fmt.Print(buf.Bytes())
   // [24 45 68 84 251 33 9 64]
   fmt.Println("send over")

   conn.Write(buf.Bytes())//向socket中写入buf
   //words := "hello world!"
   //conn.Write([]byte(words))

}



func main() {
   server := "127.0.0.1:8090"
   tcpAddr, err := net.ResolveTCPAddr("tcp4", server)//转换成TCP地址
   if err != nil {
      fmt.Fprintf(os.Stderr, "Fatal error: %s", err.Error())
      os.Exit(1)
   }

   conn, err := net.DialTCP("tcp", nil, tcpAddr)//进行TCP连接
   if err != nil {
      fmt.Fprintf(os.Stderr, "Fatal error: %s", err.Error())
      os.Exit(1)
   }


   fmt.Println("connect success")
   sender(conn)//发送请求

}