Public Structure Packet
    Dim Time() As Byte
    Dim Var1 As Byte
    Dim Var2 As Single
    Dim Var3 As Single
    Dim ID As Long
End Structure
 
Public Class Form1
 
 Private Port As Integer = 12345
 
 
 ' Funktion ist nur kopiert^^ (CodeProject)
 Private Function BulidStr(ByVal Buff() As Byte, ByVal MyType As System.Type) _
   As Object
 
        Dim MyGC As GCHandle = GCHandle.Alloc(Buff, GCHandleType.Pinned)
 
        Dim Obj As Object = Marshal.PtrToStructure(MyGC.AddrOfPinnedObject, _
          MyType)
        Return Obj
 
        MyGC.Free()
 
 End Function
 
 Private Sub StartListener()
 
        Dim Listener As New UdpClient(Port)
        Dim EndPoint As New IPEndPoint(IPAddress.Any, Port)
 
        Dim Pack As Packet
 
        Try
 
                Dim Data As Byte() = Listener.Receive(EndPoint)
 
                Pack = BulidStr(Data, Pack.GetType)
 
        Catch ex As Exception
            MsgBox(ex)
        Finally
            Listener.Close()
        End Try
    End Sub
End Class

	Public Structure Packet
		<MarshalAs(UnmanagedType.ByValArray, Sizeconst:=12)> Dim Time As Byte()
		Dim Var1 As Byte
		Dim Var2 As Single
		Dim Var3 As Single
		Dim ID As Long
	End Structure

Private Function BulidStr(ByVal buff() As Byte, ByVal myType As System.Type) As _
  Object
	'Sicherheitscheck, dass wir genug Daten im Buffer haben
	If buff.Length < Marshal.SizeOf(myType) Then
		Throw New ArgumentException(String.Format("Das Array hat nicht genug" & _
  "Elemente, um ein Objekt vom Typ {0} zu erstellen", myType))
	End If
 
	Dim MyGC As GCHandle = GCHandle.Alloc(buff, GCHandleType.Pinned)
	'Try-Finally, um MyGC.Free() auch bei Fehler auszuführen
	Try
		Dim p As IntPtr = MyGC.AddrOfPinnedObject()
		Dim o As Object = Marshal.PtrToStructure(p, myType)
		Return o
	Finally
		MyGC.Free()
	End Try
End Function

Public Class Form1
 
    Private Const Port As Integer = 12345
    Private Packet As Test
 
    Private Structure Test
 
        Dim Var1() As Byte
        Dim Var2() As Byte
        Dim Var3() As Byte
        Dim Var4 As Byte
        Dim Var5 As Single
        Dim Var6 As Long
 
    End Structure
 
    Private Sub StartListener()
 
        ReDim Packet.Var1(3)
        ReDim Packet.Var2(3)
        ReDim Packet.Var3(1)
 
        Dim Done As Boolean = False
        Dim Listener As New UdpClient(Port)
        Dim EndPoint As New IPEndPoint(IPAddress.Any, Port)
 
        Dim Pt As Integer
 
        Try
 
            While Not Done
 
                Dim Data As Byte() = Listener.Receive(EndPoint)
 
                Pt = 0
 
                Array.Copy(Data, Packet.Var1, Packet.Var1.Length)
                Pt += Packet.Var1.Length
                Array.Copy(Data, Packet.Var2, Packet.Var2.Length)
                Pt += Packet.Var2.Length
                Array.Copy(Data, Packet.Var3, Packet.Var3.Length)
                Pt += Packet.Var3.Length
 
                Packet.Var4 = Data(Pt)
                Pt += 1
 
 
                Packet.Var5 = BitConverter.ToSingle(Data, Pt)
                Pt += 4
                Packet.Var6 = BitConverter.ToInt64(Data, Pt)
                Pt += 8
 
                MsgBox(Encoding.ASCII.GetString(Packet.Var1, 0, _
                  Packet.Var1.Length)
 
            End While
 
        Catch ex As Exception
            MsgBox(ex.Message)
        Finally
            Listener.Close()
        End Try
 
    End Sub
End Class

Public Class Form1
 
    Private MainThread As Thread = New Thread(AddressOf StartListener)
 
    Private Port As Integer = 12345
    Private ID As Integer = 1
 
    Private Done As Boolean = False
    Private Packet As Test
 
    Private Structure Test
        Dim Time As UInteger
        Dim Var1 As Single
        Dim ID As Integer
    End Structure
 
    Private Sub Form1_Load([...]) Handles MyBase.Load
        MainThread.Start
    End Sub
 
    Private Sub Form1_FormClosing([...]) Handles MyBase.FormClosing
        Done = True
        MainThread.Abort
    End Sub
 
    Private Sub StartListener()
 
        Dim Buffer1 As Test
        Dim Buffer2 As Test
 
        Dim Listener As New UdpClient(Port)
        Dim EndPoint As New IPEndPoint(IPAddress.Any, Port)
 
        Dim Pt As Integer
 
        Try
 
            While Not Done
 
                Dim Data As Byte() = Listener.Receive(EndPoint)
 
                Pt = 0
                Buffer1.Time = BitConverter.ToUInt32(Data, Pt)
                Pt += 4
                Buffer1.Var1= BitConverter.ToSingle(Data, Pt)
                Pt += 4
                Buffer1.ID = BitConverter.ToInt32(Data, Pt)
                Pt += 4
 
                If Buffer1.ID = ID Then
 
                    Select Case Buffer1.Time
                        Case Is > Buffer2.Time
 
                            Buffer2 = Buffer1
 
                        Case Else
 
                            Buffer2 = Buffer1
                            Buffer1 = Packet
 
                    End Select
 
                    Packet = Buffer2
 
                End If
 
            End While
 
        Catch ex As Exception
            MsgBox(ex.Message)
        Finally
            Listener.Close()
        End Try
 
    End Sub
End Class

________
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