GO語言UDP小筆記

這是一個建立於 的文章，其中的資訊可能已經有所發展或是發生改變。

<pre style="margin-top: 0px; margin-bottom: 0px;"><span style=" color:#0000ff;">package</span><span style=" color:#f57900;"> </span>main

import (

    "fmt"

    "net"

    "time"

)

func main() {

    udpaddr, err := net.ResolveUDPAddr("udp", "127.0.0.1:1789")

    if err != nil {

        fmt.Println(err)

        return

    }

    lis, err := net.ListenUDP("udp", udpaddr)

    if err != nil {

        fmt.Println(err)

        return

    }

    defer lis.Close()

    for {

        buf := make([]byte, 512)

        n, addr, err := lis.ReadFromUDP(buf)

        if err != nil {

            fmt.Println(err)

            continue

        }

        str := string(buf[:n])

        go func(lis *net.UDPConn, addr *net.UDPAddr, body string) {

            lis.WriteToUDP([]byte(body), addr)

            time.Sleep(3e9)

        }(lis, addr, str)

    }

}

package mainimport ("bytes""encoding/json""fmt""io""net""os")type Fileinfo struct {Name stringPath string}func server() {laddr := &net.UDPAddr{IP: []byte{127, 0, 0, 1}, Port: 1789}con, err := net.ListenUDP("udp", laddr)if err != nil {fmt.Println(err)return}defer con.Close()for {Buf := make([]byte, 1024)n, raddr, _ := con.ReadFromUDP(Buf)var info Fileinfojson.Unmarshal(Buf[:n], &info)if info.Name != "" {if info.Path != "" {e := os.Chdir(info.Path)if e != nil {con.WriteTo([]byte(e.Error()), raddr)continue}}con.WriteToUDP([]byte("OK"), raddr)File, _ := os.Create(info.Name)defer File.Close()for {Buf := make([]byte, 4096)n, r, _ := con.ReadFromUDP(Buf)if r.String() != raddr.String() {continue}if n == 4 && bytes.Contains([]byte{0, 69, 79, 70}, Buf[:n]) {File.Sync()File.Close()break}File.Write(Buf[:n])}}}}func client() {con, e := net.Dial("udp", "127.0.0.1:1789")if e != nil {fmt.Println(e)return}defer con.Close()var info Fileinfo = Fileinfo{Name: "WinMD5.exe", Path: "D:"}b, _ := json.Marshal(info)con.Write([]byte(b))Buf := make([]byte, 1024)n, _ := con.Read(Buf)if string(Buf[:n]) == "OK" {File, _ := os.Open("3.go")for {Buf := make([]byte, 4096)n, e := File.Read(Buf)if e != nil {if e == io.EOF {break}fmt.Println(e)break}con.Write(Buf[:n])}con.Write([]byte{0, 69, 79, 70})}}