first asking an question and then introducing but i kinda need some help in here.First of all im not new to VB, But i am to VB.NET and espessially socket programming.Now i need an way to send the lenght of the string being send in bytes before the string itself so <lenghtinbytes><string>.
ive tried so many things, and its possible because the client itself does it too...but just cant find an way.
[Code]...
I'm trying to send a 28 character string to a remote ip address and port. I've done this successfully in vb.net using the following code snippets:
Dim swon As String = "A55A6B0550000000FFFBDE0030C8"
Dim sendBytes As [Byte]()
sendBytes = Encoding.ASCII.GetBytes(swon)
netStream.Write(sendBytes, 0, sendBytes.Length)
I now have to convert this across to c++ and have the following so far:
char *swon = "A55A6B0550000000FFFBDE0030C8";
array<Byte>^ sendBuffer = gcnew array<Byte>(bufferSize);
sendBuffer = BitConverter::GetBytes( swon );
tcpStream->Write(sendBuffer, 0, sendBuffer->Length);
but am getting stuck at this point. I'm sure I'm missing a simple syntax error but I can't figure it out!To clarify, I'm not getting an error, but I don't think the string is being converted to bytes correctly as when I convert back, I just get a '01'
I am using sockets and such for a while now, and want to go an step further in this. Now for example lets say an client would send [lenghtofstringinbytes]string[somethingelseinbytes]another thing.
How can I send/read/parse it?
Now I am doing this:
Private Sub onDataArrival(ByVal ar As IAsyncResult)
Try
Dim obj_SocketState As StateObject = CType(ar.AsyncState, StateObject)
Dim obj_Socket As Socket = obj_SocketState.WorkSocket
Dim sck_Data As String
[Code] .....
So using Getstring for it, but thats not the way for this as you get nothing else but an empty string back. So I have to parse it without converting it to an string.
I am building an application in which sends an outside server data, it then shoots back data which pertains to what I sent. The problem that I am having is that the maximum amount of bytes tha will come back is 8001. The program works fine as long as the return byte value is less then 8001. Something with the max value sounds familiar but I can not pin point it. What else could I do to receive the rest of the data? This code snippet is where im getting problem:[code].....
View 1 Repliesi have a task to create a TCP Server (a program that is listening on its network card interfaces for incoming data stream).I have search on the internet and i found that i can use two methods : Socket or TCPListener class.I have created an example for Socket class, but i wondering how could i test it? I need to check that if another computer in the network send some string data to the listener computer , then this message should be displayed.Here is the example from microsoft that i am using for TCP Server using Socket:
Public Shared Sub Main()
' Data buffer for incoming data.
Dim data = nothingc[code]....
But it does not work because of the PORT setting.If in the TCP Server i have "Dim localEndPoint As New IPEndPoint(ipAddress, 0)" the client crashes, but if i change the port from any (0) to 11000 for example,the client works fine.Do you know why?
Later edit2:Maybe i should have started with this question:Which method is recommended for my scope?asynchronous or synchronous method ?
This code will allow you to send Emails using only .NET Sockets. This code was adapted from sample code on[code]...
View 7 RepliesSo basically I would like to know what goes on behind smtpclient, webrequest and all those.
I would like to know if its possible to connect to an smtp server with sockets. Also, can anyone recommend a good OOAD(object oriented analysis and design) tutorial or book?
I want to send image from server to client via .net Sockets and assign it to a picturebox. but I got problem in receiving data, it's 'Server' side code:
[Code]...
I'm completely new to sockets etc.I'm trying to create an app that'll allow someone to send short information messages to several other people with the same app, using the internet and sockets(?)I've tried using code from online, but I'm getting no where.
View 4 RepliesI have an array of IP addresses, and I want to send the same data to all of them. I could just send the loop code that sends data but I think there's a better way of doing this.
View 1 RepliesI'm writing a replacement for an old library we use at the office to communicate with a rather clumsy and old custom-made C++ framework that takes requests via sockets in order to communicate with a bunch of other systems. The problem is that it will only take plain text messages containing a string which must be formatted in a very specific way.The problem I'm facing is that I haven't found so far a way of sending plain text through the socket. The Send method of the socket will only take byte arrays, and while the listening point receives the data, it gets there completely scrambled, and there's no way I can mess with that in order to convert the byte array back to plain text. I need to be able to send plain text, not byte arrays.[code]
View 1 RepliesI have written a windows service that uses sockets to send receive data, it works fine when the server has been running and all other services have started, but after a reboot it does not work. Now I know its probably dependant on another service and I know how to add dependencies, but how do I work out which services its dependent on?
View 1 RepliesI have created a Client that can send and receive data via TCP sockets. The objects stored on the serverside are the *exact* same object used for the client. They use the same send and receive protocols.
Now, when i send a string from the server to the client , it does precisely what it should do. However when I send a string to the server.... I do receive the string as an equal length of NULL characters. I run the server and client locally.
Basicly what can influence the behaviour between two completely identical objects performing the exact same task? I wonder if there is some socketflag issue if the TCPlistener.accept function returns a completely different setup then the one I R used to.
(if it is of any interest, the send protocol is asynchronious)
I would like to use the USB port power as source and use the an amplifier on D+/D- Twisted Pair signal wires as my command line. I saw a thread suggesting to use the output as PWM. How can I send a single byte or stream of bytes to the port. Is it possible to read status of the D+/D- if they are shorted together?
View 7 RepliesI didn't found any performance counter that would monitor an process's/thread's network bandwidth and not just that of an ethernet card.
So I could see how much bytes did an application receive and send.
Did I miss something or is there another way?
I want to send data of bytes from .net server to flash client. i have created a simple .net tcp server but what code would i need to create the flash tcp client in order to receive bytes NOT string or xml, just bytes?
View 1 RepliesI'm attempting to discard the contents of a System.Net.Sockets.Socket send buffer using theSocket.IOControl(IOControlCode.Flush, .... Does anybody know whether VB.NET supports this command? I've tried supplying 'Nothing' and 'Nothing' for both required parameters, also empty and populated byte arrays in combination with 'Nothing' for both required parameters, but I consistently get an 'Invalid argument' exception. I've tried a web search for an answer, but the only mention I've found was a question asked about 8 years ago, with still no answer.
View 1 Replieswhen i transfer the bytes sent by the client program to a string the string length is affected.when i put the bytes sent by the client program to a message box. it returns the corrrect text. but when i check the length it will return 8192 or higher. but the actual size is just 5.
My Code
Dim tcpClient As TcpClient = tcpListener.AcceptTcpClient()
RichTextBox1.Text = RichTextBox1.Text & vbNewLine & "Connection accepted."
' Get the stream[code]....
I am using Nektra's Deviare to hook winsock's send method calls. My ideia is to learn to also send messages through the same socket than the original application. So what I'm doing is when i detect the first call to send message, I save the socket id(the first argument of the send function), so I can use it later.
So here is my code:
uint socket = 0;
[DllImport("Ws2_32.dll")]
private static extern int send(uint socket, string buf, int len, int flags);
[Code].....
This last messagebox is poping up always -1. Why should be it?
edit: calling WSAGetLastError() returns 2. Which I do not know what it means, as it doesn't seem to appear on msdn.
I've been trying to reuse my bosses vb.net buildpacket code which he has successful used for Serial programming eg. SerialPort1.Write(buildpacket(useraddress,252,"0006","0") for the function listed below.My challenge.Create equivalent functionality for Socket BeginSend() which requires a byte array.Whether modifying the vb.net below or getting a c# equivalent to work, it has been repeatedly recommended to scrap the string concatenation approach for which I have to use Encoding.BigEndianUnicode.GetBytes() and then getting rid of extra bytes with zero values.
I'm lacking in imaging something different which would work for socket programming directly and allow me to eliminate all the hassles that c# integer conversions into string value that can be encoded trouble free.I would need to call the equivalent of the following that would return a byte array rather than a string with the following arguments
1. Source address (0-255)
2. Destination address (0-255)
3. Function code ("0001" through "0100")
4 Packet Data Unit (pdu - some integer value
[code]....
It's become a night mare. All day today I have been trying to tell the hex contents of the bytes in a string. In this case Im attentpting to detect a VBCRLF. In the debugger this in displayed as a " " and thats it no matter how I have to setting set.It makes it difficult doesn't it? The thing is that debuggers are quite capable of displaying adresses, of course this is only relevant to systems that do not change virtual addresses (which Windows does not)only physical addresses.Why is it impossible to see the values of a vbcrlf (0D0A) in a string? This sytem is becoming impossible to use.
"MODERN PROGRAMMING is deficient in elementary ways BECAUSE of problems INTRODUCED by MODERN PROGRAMMING." Me
Im making a database converter (phpbb to ipb)I noticed during analysing both databases that the posts of phpbb are converted to bytes as you can c here
-- Table structure for phpbb_posts
-- ----------------------------
CREATE TABLE `phpbb_posts` ([code]....
I want to convert those to regular text again but I have no clue how to script my converter to lookup the bytes place (after 0x) converts the string (as the bytes arent in array) and where to stop converting the bytes (after the ,)then replace the bytes text by the regular text and this needs to be in a loop because all posts need to be converted to normal text.
I have string, what contains bytes... (Example below)
And I need convert these bytes into text... But I really don't know how...
Code (For Better understand):
CODE:
and now, how to convert it into text? (The Result text in "ProductName", BTW)(I don't want to use Hex Editor still )
I've got the following simple code to convert Bytes to a Hex string :-
Code:
Shared Function BytesToHex(ByVal bytes() As Byte) As String
If bytes Is Nothing Then Return ""
Dim S As String = BitConverter.ToString(bytes)
[Code].....
The HexToBytes routine obviously can take a lot longer to complete than the BytesToHex routine and is noticeably slower when dealing with a lot of data. As I'm converting a lot of hex strings back to bytes, I wondered if there was a more efficient way of doing it without looping through the whole string as I am doing?
Ive 2 buttons and 3 text boxes.Button 1 encrypts the data from textbox1 to bytes, converts it to string and display it in textbox2.Button 2 reads string from textbox2, converts it to bytes and decrypts it displaying it in textbox3 (textbox1 and 3 got to match).The encrypt/decrypt process works fine but the conversion from string to bytes is failing and cannot seem to find the problem. The error states that the string doesnt have the same format (Bytes(i) = Byte.Parse(Values(i))
[Code]...
This has to be incredibly simple, but I must not be looking in the right place.
I'm receiving this string via a FTDI usb connection:
'UUU'
I would like to receive this as a byte array of
[85,85,85]
In Python, this I would convert a string to a byte array like this: [ord(c) for c in 'UUU']
I've looked around, but haven't figured this out. How do I do this in Visual Basic?
I want it to do is that you input a string, then you select an algorithm (Theres only going to be one RijnDael) then you input a key, then the Initialization Vector comes from "txtIV.text" then you select the key bytes and the block bytes from the numeric up/down, then you either encrypt or decrypt.
View 1 RepliesOk i am having some issues designing a base-class to handle generics.Caveat is i need to restrict the type put in as a Numeric type, specifically Int16, Int32, or Int64 (Short or Long).I know you can do Of T as {Structure} but i dont want to select the key bytes and the block bytes from the numeric up/down.
View 2 RepliesI am working on a project that needs to send hex bytes ie.Sub receives an integer like 276 and then performs
Dim CmdBuf() As Byte = New Byte() {Byte1, Byte2}
strHex = Hex(intNumber) which makes strHex equal to 114 in hex...
Next I need to break into separate bytes something like
Byte1 = Left(strHex, 1)
Byte2 = Right(strHex, 2)
But this does not work......Hex value of 114 needs to be converted into a couple of bytes like &H1 &H14 to be sent out the serial port.
.Write(Buf, 0, 2)
How can I do this?
I need to basically search for either a string such as "I-AM-RIGHT-OVER-HERE" or search for a sequence of bytes and return the offset of where that string or byte sequence is at.
View 1 Replies