L'envoi de données UDP, y compris à l'aide de hex VB.NET

Vous pouvez mettre ensemble un quickie décodeur comme celui-ci:

Function HexCodeToHexChar(ByVal m as System.Text.RegularExpressions.Match) As String
    Return Chr(Integer.Parse(m.Value.Substring("<0x".Length, 2), _
         Globalization.NumberStyles.HexNumber))
End Function

puis de les utiliser pour transformer:

Dim r As New System.Text.RegularExpressions.Regex("<0x[0-9a-fA-F]{2}>")
Dim s As String = r.Replace("abc<0x44>efg", AddressOf HexCodeToHexChar)
' s should now be "abcDefg"

vous pouvez aussi faire un codeur fonction qui annule ce décodage (bien qu'un peu plus compliqué)

Function HexCharToHexCode(ByVal m As Match) As String
    If m.Value.StartsWith("<0x") And m.Value.EndsWith(">") And m.Value.Length = "<0x??>".Length Then
        Return "<0<0x78>" + m.Value.Substring("<0x".Length)
    ElseIf Asc(m.Value) >= 0 And Asc(m.Value) <= &HFF Then
        Return "<0x" + Right("0" + Hex(Asc(m.Value)), 2) + ">"
    Else
        Throw New ArgumentException("Non-SBCS ANSI characters not supported")
    End If
End Function

et de l'utiliser pour transformer:

Dim r As New Regex("[^ -~]|<0x[0-9a-fA-F]{2}>")
Dim s As String = r.Replace("abc"+chr(4)+"efg", AddressOf HexCharToHexCode)
' s should now be "abc<0x04>efg"

ou vous pouvez simplement construire la chaîne de caractères spéciaux dans les il pour commencer comme ceci:

Dim packet As String = Chr(&H01) + "Z30" + Chr(&H02) + "AA" + Chr(&H06) + _
    Chr(&H1B) + "0b" + Chr(&H1C) + "1" + Chr(&H1A) + _
    "1This message will show up on the screen" + Chr(&H04)

pour l'envoi d'un paquet UDP, ce qui suit devrait suffire:

Dim i As New IPEndPoint(IPAddress.Parse("192.168.0.5"), 3001) ''//Target IP:port
Dim u As New UdpClient()
Dim b As Byte() = Encoding.UTF8.GetBytes(s) ''//Where s is the decoded string
u.Send(b, b.Length, i)

OriginalL'auteur Hafthor

Le client UDP envoie un tableau d'octets.

Vous pouvez utiliser un flux de mémoire et d'écrire des octets dans un tableau.

Public Class MainClass
Shared client As UdpClient
Shared receivePoint As IPEndPoint
Public Shared Sub Main()
receivePoint = New IPEndPoint(New IPAddress(0), 0)
client = New UdpClient(8888)
Dim thread As Thread = New Thread(New ThreadStart(AddressOf WaitForPackets))
thread.Start()
Dim packet As Packet = New Packet("client")
Console.WriteLine("Sending packet containing: ")
Dim data As Byte() = packet.Data
client.Send(data, data.Length, "localhost", 5000)
Console.WriteLine("Packet sent")
End Sub
Public Shared Sub WaitForPackets()
While True
Dim data As Byte() = client.Receive(receivePoint)
Console.WriteLine("Packet received:" & _
vbCrLf & "Length: " & data.Length & vbCrLf & _
System.Text.Encoding.ASCII.GetString(data))
End While
End Sub ' WaitForPackets  
End Class  
Public Class Packet  
Private _message As String  
Public Sub New(ByVal message As String)
_message = message
End Sub
Public Function Data() As Byte()
Dim ret(13 + _message.Length) As Byte
Dim ms As New MemoryStream(ret, True)
ms.WriteByte(&H1)
'<0x01>Z30<0x02>AA<0x06><0x1B>0b<0x1C>1<0x1A>1This message will show up on the screen<0x04>  
ms.Write(System.Text.Encoding.ASCII.GetBytes("Z30"), 0, 3)
ms.WriteByte(&H2)
ms.Write(System.Text.Encoding.ASCII.GetBytes("AA"), 0, 2)
ms.WriteByte(&H6)
ms.Write(System.Text.Encoding.ASCII.GetBytes("0b"), 0, 2)
ms.WriteByte(&H1C)
ms.Write(System.Text.Encoding.ASCII.GetBytes("1"), 0, 1)
ms.WriteByte(&H1A)
ms.Write(System.Text.Encoding.ASCII.GetBytes(_message), 0, _message.Length)
ms.WriteByte(&H4)
ms.Close()
Data = ret
End Function
End Class

OriginalL'auteur Hamish Smith