Detect Individual SYN Or FIN Packets?
Mar 16, 2011Can I send and detect individual SYN or FIN packets using VB.NET Sockets or any other process in VB.NET?
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Display Individual Parts With Individual Prices
Jul 11, 2011So I have a code atm that has 2 combo boxes, one to select the make, then it will enable the model, I have 3 model choices, here's code: [code] Once I have selected my model of the car, it takes me to that specific form with a picture of that model, I then want to display individual parts, with individual prices that will add up in a text box above.
View 2 RepliesReading Packets From UDP / IP
May 13, 2009I am writing a program that talks back and forth with an external machine through UDP/IP. I have figured out how to talk to the machine, bu now I need to know how to read the machine's response. I am using the following code:
Dim receiveBytes As [Byte]() = udpClient.Receive(RemoteIpEndPoint)
Dim returnData As String = Encoding.ASCII.GetString(receiveBytes)
TextBox1.Text = returnData
When I break the code down and read receiveBytes, it comes through exactly the way I want it. It is falling apart when it gets encoded and put into a textbox. It just comes out as a "?".
Receiving UDP Packets From Different Ip's?
Jun 19, 2009I am trying to receive about 900 packets coming from around 900 different ip's. But for some reason I can't seem to capture them all. The same code in C++ seems to work fine, but when I try to do it and run it through the parser it seems that I only get about 150 - 300 of these packets each time I ask for them.
[Code]....
TCP: Differentiate Between Packets?
Oct 3, 2010Does anyone know of a good example of TCP, in C# or VB.NET?
The problem I have with the majority i've found is that they send data once, receive data once, and end. This isn't a workable example. Even MSDN's example does this.
My main question:
Every example reads incoming data into a buffer (byte array), usually 512 bytes. If two packets are received in a row, how do I know where one packet's data ends and another's begins? What if a single packet has more than 512 bytes of data?
All TCP examples i've found work in a rather procedural way.
I'd like to have something as simple as this:
Code:
Public Sub OnPacket(data As Byte())
End Sub
Receive And Send Packets?
Jul 25, 2009Since a few months I want to learn how to receive and send packets. Since WinSock doesn't work I think it'll be quite hard to get an easy way to do it.
I want to be able to send and get packets as a client. (TCP) I know that I need System.Net.Sockets, and that's quite everything...
Way To Send Parsed Packets
Mar 8, 2011I am on a new topic in VB.NET and I am so confused I don't really even know where to start. It is sending Parsed Packets. This packet below is a login server of a game and I want to know how to send it so it automatically does it.[code]....
View 6 Replies.NET Asynchronous Sockets Packets Getting Lost?
Oct 15, 2011I made a TCP server which communicates with multiple clients at once, but I can't seem to be able to make them stable. When one of the client sends 100 packets to the server, the server receives only a few of them.Here's the client code in PasteBin. It shows how the client connects to the server and then sends 100 messages in a For loop to the server.And here's how the server handles the connection. I couldn't paste the full source as it's hundreds of lines long so let me know if it's missing any mandatory parts and I'll upload them as well.
View 1 RepliesNot Receiving All Packets - VB Sockets - Async?
Oct 27, 2009Here's the code on the sending side of my sockets:
Private Sub Send(ByRef Buffer() As Byte)
Dim obj_StateObject As New StateObject
obj_StateObject.WorkSocket = m_tmpSocket
[code].....
Sending Raw Packets To WebBrowser Control?
Feb 15, 2009Well I need to send a raw packet to a Web Browser Control. The packet is:
"%xt%z%zo%50% . 1000000 . "%""
I need to send it to a flash game but I have no idea how to.
Use Packet X To Capture Packets From A Certain Program That Uses UDP?
Jun 12, 2011I have been trying to figure out how to use Packet X to Capture Packets from a certain program that uses UDP. Does anyone know how to do so?
View 1 RepliesVS 2008 - Handle Packets When It Comes In Parts?
Jul 6, 2011I have a program which uses TcpClient, the issue I'm having is how do I construct the packets when some of them come in seperate parts. For example, If I receive 5 packets, 2 of them are fine, but the other 3 have come in seperate parts when it's suppose to be a whole packet. How can I handle this?
View 5 RepliesVS 2008 - Time Stamps On Sent Packets
Aug 20, 2009Im sending packets through UDP, and want to get the time it takes for the server to receive the packet from the client. Would the best way be by adding a timestamp to the packet the client sends, and then use that time with the server to calculate the actual time it took to receive?
View 39 RepliesVS 2008 Sending Packets To A IP Address?
Dec 28, 2009Hey there, I thought i would redo my question, How could i send packets in VB to a IP and Port, I'm unsure on how to do this could somebody tell me?
View 4 RepliesWhy Is Socket.BeginReceive Losing Packets From UDP
Sep 25, 2010The following code waits for data over UDP. I have a test function that sends 1000 packets (datagrams?) of 500 bytes each. Each time I run the test function, the receiver gets only the first few dozen packets but drops the rest. I looked at the incoming network data using Wireshark and I see all 1000 packets are actually received, but just don't make it to may app's code.[code]If I add a small delay after each call to Send, more packets make it through; however since Wireshark says that they were all received anyways, it seems that the problem is in my receive code. I should mention that UdpListen is running on a separate thread.Any idea why I am dropping packets? I also tried UdpClient. BeginReceive/ EndReceive but had the same problem. A second issue that bothers me is the global nature of the receive buffer when using Sockets and I am not sure if I don't process incoming packets quickly enough that the buffer will be overwritten.
Based on the various, somewhat conflicting suggestions from replies to this and other posts, I made some changes to my code. Thanks to all who chimed in various bits; I now get all my packets from dial-up to Fast Ethernet. As you can see, it was my code at fault and not the fact that UDP drops packets (in fact I have not seen more than a tiny percentage of packets being dropped or out of order since my fixes). Differences:
1) Replaced BeginReceive()/EndReceive() with BeginReceiveFrom()/EndReceiveFrom(). By itself this had no notible effect though.
2) Chaining BeginReceiveFrom() calls instead of waiting for the async handle to set. Not sure if any benefit here.
3) Explicitly set the Socket.ReceiveBufferSize to 500000 which is enough for 1 second worth of my data at Fast Ethernet speed. Turns out this is a different buffer than the one passed to BeginReceiveFrom(). This had the biggest benefit.
4) I also modified my send routine to wait a couple of ms after having sent a certain number of bytes to throttle based on expected bandwidth. This had a big benefit for my receiving code even though Wireshark said all my data still made it across even without this delay.
I did NOT end up using a separate processing thread because, as I understand it, each call to BeginReceiveFrom will invoke my callback on a new worker thread. This means that I can have more than one callback running at the same time. It also means that once I call BeginReceiveFrom I have time to do my stuff (as long as I don't take too long and exaust the available worker threads).[code]What is not shown above is the error handling and dealing with UDP data being out of order or missing.I think this handles my issue, but if anybody still sees anything wrong with the above (or something I could do better) I would love to hear about it.
Make A Packet Sniffer That Will Give SSL Packets
Oct 11, 2010I need to make a packet sniffer that will give me SSL packets. It doesn't need to give me any other information than the body of the packet, the actual data being sent to me. It does not need to differentiate between different IP addresses. And, it doesn't even need to differentiate between things which are and are not SSL packets. Any packets will be fine, it just needs to support SSL packets. The fewer lines of code the better...
View 5 RepliesSend Separate Packets From Server To Client?
Oct 1, 2009Now i need to send separate packets from the server to the client.For the client I am using usual Tcp but for the server I am using Winsock Control. [code]...
View 5 RepliesVS 2008 Empty Values In Packets Disappear - TCP?
Jun 10, 2010Empty values in byte array at the end of one packet are replaced by beginning values of the next packet sent in TCP connection. How may I avoid this?
View 4 RepliesVS 2010 Sniff Packets From A Specific Application
Feb 14, 2011I'm trying to sniff packets from a specific application. I searched around but couldn't find anything useful, but I did hear something about WinPcap. What is WinPcap and how do I use it? Also, is there another way to sniff packets?
View 6 RepliesCommunications :: Could Lost Packets Interfere With Network Operation
Jul 29, 2008At my workplace I have been developing a server/client application which receives on port 8000 and sends on 8001. We do not have any other applications that use these ports, but we do have an application that accesses an SQL database in which part data is stored.
When I am doing testing on the application, if the server were to crash while the client app was sending a packet, could this lost packet cause issues with the network at all?I ask because for some reason we have been receiving connection timeout errors from the application that stores our product data, but we haven't made any changes or started running any new jobs on the network that I am aware of.
Communications :: Used To Assemble And Send Raw Packet / Receive Response Packets?
Sep 14, 2008What Visual Basic code can be used to assemble and send a raw packet, and receive response packets? I looked on MSDN and I couldn't find any documentation for anything used to send a packet.
View 2 RepliesVS 2008 Socket Application - Transfer Packets From The PC To The Mobile Phone
Nov 2, 2009i try to transfer packets from the PC to the Mobile phone~ my PC is act as a Server and Mobile as a Client. My Mobile is successfully connect to my PC, but when i try to pass a packets from Mobile, it went failed without any error. The Server didn't receive any packets from Mobile. i had test my code on PC to PC and it's work fine. Anyone have this kind of experience?
View 3 RepliesVS 2010 Tcp Client Application Mixes Up The Order Of Received Packets?
Oct 22, 2010I have written a simple Server application that transmits an XML string to all connected clients when the user updates/alters a datagridview. When I connect to this server with telnet I can see the correctly formed xml string.
I have also written a client application, which on reception of the Xml string, displays it in a datagridview. But When I look at the xml string it is either missing parts of in the wrong sequence.
[Code]...
If The Packet Received Is Over A Certain Size, The Socket Then Fails To Receive Anymore Packets/data After It?
Jul 4, 2011I'm writing a program which uses sockets, Now the issue I'm having is, If the packet received is over a certain size, the socket then fails to receive anymore packets/data after it.
View 3 Replies"drop Icmp Packets And Not Reply To Them"
Jul 11, 2009I am trying to make a program that will stop people on the same network being able to tale if im online by pinging my i.p adress aparantly the only way of doing this is to "drop icmp packets and not reply to them"
dose anyone know how to do this? and can anyone provide me with a basic script that will do this?
How To Set Variable To Individual Row
Feb 16, 2011Basically I'm designing a program atm for my college coursework and have been trying to get a search button to work. Basically, I need a way so that after the customer id has been found, my variable (in this case inc) needs to set itself to the row which the customer id that has been found is in. the idea is that it finds the row, and fills in the textboxes which I have with the data Here's the bit of code I have atm: (And btw, inc is set as an integer earlier on in the program)
Dim CustomerID As Integer
'asks for the customer's ID number so that their results can be found.
CustomerID = Val(InputBox("what is the Customer number?"))
Try
Sql = "Select * from tblQuotes WHERE CustomerID = " & CustomerID
[Code] ....
Hopefully with the text Whatever the Row Number is being replaced by actual code to get it to that row.
Getting Individual List Items?
Apr 23, 2012I have thius code that gets the html results of google search
Private Sub WebBrowser1_DocumentCompleted(ByVal sender As System.Object, ByVal e As System.Windows.Forms.WebBrowserDocumentCompletedEventArgs) Handles WebBrowser1.DocumentCompleted
Dim PageElements As HtmlElement = WebBrowser1.Document.GetElementById("rso")
TextBox2.Text = PageElements.OuterHtml
Dim text = TextBox2.Text
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
WebBrowser1.Navigate(TextBox1.Text)End SubAnd it returns the html code.I want to get each list item and takes it html and put each individuals html in to a variable. How would this be done.
How To Use Individual Characters In A Textbox
Oct 30, 2011I have a a multiline textbox, I want to take each and every character that the user enters and on a button press it replaces them with a set of characters, like:
i with x75d
or:
f with g8r
but the only way i have figured out how to do something like this is using a character in between each character and the split method, like:
Dim input() As String
Dim txt as String
Private Sub Encode_Click(ByVal sender As System.Object, ByVal e As
[Code]....
Individual Elements In A Collection?
Jan 7, 2010I'm converting a library from C# to VB.net which so far hasn't been too difficult. One class though implements IEnumerable and IEnumerator and contains a block of code like this:
public class MyClassCollection
{
// Assume all other necessary code is in place
[code].....
Picking Up Individual Keys?
Feb 10, 2009I am making a HTML editor and thats the easy par ie saving as .html etc, but i want to also add in the thing thats in VB wherein it picks up the word your typing and make suggestions, i have made it so it can have a data base of a thousand words (1000) and you can add and it loads all fine. Now i need to add in the functionallity to read every Key, i tryed
Code:
If e.KeyCode = Keys.Space Then Scan = ""
But none of this works, is there a better way of getting the the key press and adding it to a string untill space is pressed in which the array is cleared.
Code:
Imports System.IO
Public Class Form1
[code]....
So say i had a Tag stored that was "HTML" then as soon as i pressed the < key it would start checking my keys then if i pressed H it would display all word is the drop down box with H at the start then if i followed it with T then M it would show HTML in the box and maby a couple of others that began with HTM, if i then hit enter it would add in the L> thus compleating it and printing "<HTML>"
