Byte - UDP

[RosarioAR]

Hi to all
I have a question in reference to receive a bytes over UDP.
Im testing with an aplication in VB6 for to send the data.

I receive the data in B4A with the next code

Sub UDP_PacketArrived (Packet As UDPPacket)

   Dim msg As String
   Dim Buffer1() As Byte

   msg = BytesToString(Packet.data, Packet.Offset, Packet.Length, "UTF8")
   Buffer1=msg.GetBytes("UTF8")

I'm sendig data from VB6 with the next code

WinsockTX.SendData (Chr(1) & Chr(2) & Chr(255))

The problem is when i send a char > to 127, in Buffer1 i'm receiving 3 negative values that representing the 128 to 255 values (i'm expecting to receive 1 negative value). This negative values are the same from 128 to 255.

Values from 0 to 127 is OK
Buffer1 = [0=1, 1=2, 2=127]

Values from 128 to 255 Fail
Buffer1 = [0=1, 1=2, 2=-17, 3=-65, 4=-67]

How can i do to receive 1 negative value for next can be transform?

I read several treads respect to that, but im confused with the three negative values..

Thanks

 

[Erel]

Basic4android (and Java) Byte type is a signed type.

It doesn't really matter if you treat it correctly. Why do you convert the bytes to string?

 

[RosarioAR]

Hi Erel.
I'm converting the byte to string using the example in Basic4android - Network

Sub UDP_PacketArrived (Packet As UDPPacket)
    Dim msg As String
    msg = BytesToString(Packet.Data, Packet.Offset, Packet.Length, "UTF8")
    Msgbox("Message received: " & msg, "")
End Sub

Can i get directly the bytes from without convert to string?
I knew that Java use signed bytes, but i expected receive a negative value for then convert this.

Can you advise?
Thanks in advance.

 

[Erel]

Can i get directly the bytes from without convert to string?

Yes. Packet.Data is an array of bytes:

Dim data() As Byte = Packet.Data
For i = 0 To Packet.Length
 Log(data(Packet.Offset + i))
Next

 

[RosarioAR]

Hi Erel, thanks! my application is working fine now!!