udp连接

服务端

package main

import (
  "fmt"
  "log"
  "net"
)
func main(){
  updaddr,err:=net.ResolveUDPAddr("udp","127.0.0.1:8003")//udp结构体
  if err != nil {
    log.Println("create udp is error")
  }
  UDPConn,err:= net.ListenUDP("udp",updaddr)//监听udp
  if err != nil {
    log.Println("create udp is error")
  }
  defer UDPConn.Close()

  buf:=make([]byte,4096)
  n,cAddr,err:=UDPConn.ReadFromUDP(buf)//读取

  fmt.Println(string(buf[:n]),cAddr)
  _,err=UDPConn.WriteToUDP([]byte("this is server info"),cAddr)//写入
  if err != nil {
    log.Println(err)
  }

}

客户端

package main

import (
  "fmt"
  "log"
  "net"
)

func main(){
  conn,err:= net.Dial("udp","127.0.0.1:8003")
  if err != nil {
    log.Println("is errors")
  }
  defer conn.Close()
  conn.Write([]byte("aaaaaaaaaaaaaaaaaaaaaaaaaaa"))
  buf:=make([]byte,4096)
  n,_:=conn.Read(buf)
  fmt.Println(string(buf[:n]))
}

udp传输文件

服务端

package main

import (
  "fmt"
  "log"
  "net"
  "os"
)
func reInfo(conn *net.UDPConn, fileName string){
  fd,_:= os.Create(fileName)
  defer fd.Close()
  defer conn.Close()
  buf:=make([]byte,4096)
  for {
    n,caddr,err:=conn.ReadFromUDP(buf)
    fmt.Println(n)
    if err != nil {
      fmt.Println("is error")
      return
    }
    if n == 0 {
      fmt.Println("finish end file content")
      return
    }

    fmt.Println("客户端",caddr,"内容:",string(buf[:n]))
    fd.Write(buf[:n])
  }
}
func main(){
  udpaddr,err:=net.ResolveUDPAddr("udp","127.0.0.1:8006")
  if err != nil {
    log.Println("udpaddr is error")
    return
  }
  UdpConn,err:=net.ListenUDP("udp",udpaddr)
  if err != nil {
    log.Println("conn is eroror")
  }
  buf:=make([]byte,1024)
  n,caddr,_:=UdpConn.ReadFromUDP(buf)
  fmt.Println(caddr)
  fileName:= string(buf[:n])

  reInfo(UdpConn,fileName)
}

客户端

package main

import (
  "fmt"
  "io"
  "log"
  "net"
  "os"
)

func sendConn(conn net.Conn, filePath string){
  defer conn.Close()
  buf:=make([]byte,4096)
  fd,_:= os.Open(filePath)
  for {
    n,err:=fd.Read(buf)
    if err == io.EOF {
      fmt.Println("read file is end")
      return
    }
    conn.Write(buf[:n])
  }
}

func main(){
  conn,err:= net.Dial("udp","127.0.0.1:8006")
  if err != nil {
    log.Println("conn is errors")
    return
  }
  lists:=os.Args
  if len(lists) != 2 {
    log.Println("is erros")
    return
  }
  filePath:= lists[1]
  fileInfo,err:=os.Stat(filePath)
  if err != nil {
    log.Println("is erros")
  }
  fileName:= fileInfo.Name()
  io.WriteString(conn,fileName)
  sendConn(conn,filePath)
}