sending large files using UDP in Visual Basic

[ieshaaa04]

Hye, I have been task to creat a UDP file transfer using Visual Basic 2019.. i can transfer small files below 64kbytes but the requirement is bigger than that.. How to modify this code for it to be able to transfer larger files atleast 1Mbytes.

below is the client and server coding.

Client :

Imports System.Net.Sockets
Imports System.Text
Imports System.IO
Imports System.Net
 
Public Class frmClient
    Private Sub btnSend_Click(sender As Object, e As EventArgs) Handles btnSend.Click
 
        Try
            Dim udpClient As UdpClient = New UdpClient(txtIP.Text, Convert.ToInt32(txtPort.Text))
            Dim fStream As FileStream
 
            Dim sendPacket() As Byte
            fStream = New FileStream(OpenFileDialog1.FileName, FileMode.Open, FileAccess.Read)
            ReDim sendPacket(fStream.Length)
            fStream.Read(sendPacket, 0, fStream.Length)
 
            Dim str As String = OpenFileDialog1.SafeFileName + " (" + fStream.Length.ToString + " bytes). Do you agree?"
            udpClient.Send(Encoding.UTF8.GetBytes(str), str.Length)
 
            Dim receivedPacket(5000) As Byte
 
            udpClient.Client.ReceiveTimeout = 6000
            receivedPacket = udpClient.Receive(Nothing)
            If Encoding.UTF8.GetString(receivedPacket) = "YES" Then
                udpClient.Send(sendPacket, sendPacket.Length)
                udpClient.Client.ReceiveTimeout = 1000
                receivedPacket = udpClient.Receive(Nothing)
                If Encoding.UTF8.GetString(receivedPacket) = "SUCCESS" Then
                    MsgBox("File transfer success.")
                Else
                    MsgBox("File transfer fail.")
                End If
            Else
                MsgBox("Server rejects file transfer request.")
            End If
 
            fStream.Close()
            udpClient.Close()
 
        Catch ex As Exception
            Console.WriteLine(ex.Message)
        End Try
    End Sub
 
    Private Sub btnBrowse_Click(sender As Object, e As EventArgs) Handles btnBrowse.Click
        Dim result As DialogResult = OpenFileDialog1.ShowDialog()
 
        If result = Windows.Forms.DialogResult.OK Then
            txtFile.Text = OpenFileDialog1.FileName
        End If
 
    End Sub
 
    Private Sub frmClient_Load(sender As Object, e As EventArgs) Handles MyBase.Load
 
    End Sub
 
End Class

Server:

Imports System.Net.Sockets
Imports System.Text
Imports System.IO
Imports System.Net
 
Public Class frmServer
    Private Sub btnListen_Click(sender As Object, e As EventArgs) Handles btnListen.Click
 
        Dim udpServer As UdpClient = New UdpClient(Convert.ToInt32(txtPort.Text))
        Dim remoteEP As IPEndPoint = New IPEndPoint(IPAddress.Any, Convert.ToInt32(txtPort.Text))
        Try
            Dim receivedPacket(5000) As Byte
 
            btnListen.Enabled = False
            txtPort.ReadOnly = True
            Me.Text = "Server - Listening"
 
            udpServer.Client.ReceiveTimeout = 3000
            receivedPacket = udpServer.Receive(remoteEP)
 
            Dim res As MsgBoxResult = MsgBox(remoteEP.ToString +
                                                " requests to transfer " +
                                                Encoding.UTF8.GetString(receivedPacket), MsgBoxStyle.YesNo + MsgBoxStyle.Exclamation, "Message")
            If res = MsgBoxResult.Yes Then
                udpServer.Send(Encoding.UTF8.GetBytes("YES"), 3, remoteEP)
                receivedPacket = udpServer.Receive(remoteEP)
                Dim res2 As DialogResult = SaveFileDialog1.ShowDialog()
                If res2 = Windows.Forms.DialogResult.OK Then
                    Dim fStream As FileStream = New FileStream(SaveFileDialog1.FileName, FileMode.Create, FileAccess.Write)
                    fStream.Write(receivedPacket, 0, receivedPacket.Length)
                    fStream.Close()
                    udpServer.Send(Encoding.UTF8.GetBytes("SUCCESS"), 7, remoteEP)
                Else
                    udpServer.Send(Encoding.UTF8.GetBytes("FAIL"), 4, remoteEP)
                End If
            ElseIf res = MsgBoxResult.No Then
                udpServer.Send(Encoding.UTF8.GetBytes("NO"), 2, remoteEP)
            End If
 
            udpServer.Close()
            btnListen.Enabled = True
            txtPort.ReadOnly = False
            Me.Text = "Server"
 
        Catch ex As Exception
            Console.WriteLine(ex.Message)
            udpServer.Close()
            btnListen.Enabled = True
            txtPort.ReadOnly = False
            Me.Text = "Server"
        End Try
 
    End Sub
 
    Private Sub frmServer_Load(sender As Object, e As EventArgs) Handles MyBase.Load
 
    End Sub
End Class