I have a class that inherits from the TcpListener, this class Shadows the Start method just to call the base Start() and the base BeginAccept Tcp Client(). From time to time the method is called but the port is not opened (netstat does not show the port open).[code]The class that uses the ExtendedTcpListener implements the IDisposable pattern and inside the Dispose the ExtendedTcpListener.Stop is called.The stop text is not present at the logs when the problems happens.
How can I ask my tcpListener to listen to particular IP on specific port? I want my tcpListener to listen to the local IP of the machine. I can get the ipaddress of the pc using Dns.GetHostAddresses(). But, if pc have multiple ip's how can I know which ip address is correct? From tcpClient class I am connecting to the server. So, I know the server ip and so I want to specify ipaddress to my tcpListener class to listen on.
If I uninstall the COM1 and reboot, it works. If I shut down (power off) and restart, I get the message below. If I uninstall then click on Scan for Hardware Changes,The given port name does not start with COM/com or does not resolve to a valid serial port. Parameter name:portName
I'm making a Visual Basic GUI application to display whether a number of my ports are open for people to know whether things like my website and my Minecraft server are open.My problem is I have absolutely no idea how to do this in Visual Basic.Basically, I'm asking for something which sends a signal to an IP with a specific port, if it is open then return true, if it's closed, return false. Similar to: http:[url]....
I need to transfer data between several computers in a network using my app. I thought of using TCP ports. how to open and use them? I only want to make a file transfer and chat app that works offline.
Public Class my_class Dim WithEvents COMPort As New System.IO.Ports.SerialPort
Public Sub FindReader() Dim ports As String() = IO.Ports.SerialPort.GetPortNames() Dim port As String For Each port In ports
[Code3]...
When it runs, it shows a single COM port "COM1". I am assured that the device attached to it is a standard 8,n,1 and uses 9,600 baud. The exception is "Acess to the port 'COM1' is denied".
I have an application which need to send data to particular system on specific port. But the application gets hang if the target system port is closed.
I Want to know if a particular Port is open on a specific IP address so that i can continue my next task. PBL (Visual Studio 2010 Ultimate)
I have written some code to check if a port is open. I'm currently trying to work with the system.net.sockets name space.I know that the easy way out would be to use AxWinsock, but I don't think the AxWinSock is very cool, nor do I think it's very professional when trying to make network applications in VB.NET.
I've got this Error message : Socket Exception Was unhandled, No connection could be made because the target machine actively refused it 127.0.0.1:1 IDK, Like I said, I'm new to the System.net.sockets namespace, I'm pretty good with other stuff in VB.NET, but when it comes to the serious stuff like the system.net.sockets namespace, I'm not so great.look at this code and tell me what I am doing wrong, I've manged to get this far, and I don't want to just give up and continue watching my movie.
I have this problem says that "the portName cannot be set while the port is open". When this errors occurred, my application on sending sms could not work. Before I edit the application can work but after making some changes and ask help in this forum, the application does not work and gives errors and it says "the portName cannot be set while the port is open".
I wrote a program that uses the following class from that site: VB.NET Tutorials - Serial Port Communication In VB.Net. The problem is that I cannot open a virtual serial port, and the second is that I want to make the communication asynchronous.
This is the subroutine which reads from the port: #Region "comPort_DataReceived" ''' <summary> ''' method that will be called when theres data waiting in the buffer ''' </summary> ''' <param name="sender"></param> [Code] .....
In VB6 I had to always check if the port was open or not. But with VB.NET and the new Serial Port control I don't see any.If SerailPort1.Open then statements. In fact when I tried to use the code I got Expression does not produce a value.So does this mean that we no longer have to check to make sure the port closed?Is there a way to check if the port is open or not?
I have a few USB devices that use standard Microsoft Virtual COM Port drivers. More specifically, I believe they use the "Usbser.sys" driver. Whenever I plug my USB devices in, they always shows up in the Device Manager as a COM port, however, sometimes I am unable to open that COM port. This problem occurs on both Windows XP SP3 and windows 7 machines (The only operating systems I have tested this on).
To be a little clearer, I can plug my USB device in, and then successfully open the COM port. I unplug my USB device, then plug it back in, and I am unable to open the COM port. The only solution to this problem is to restart my PC. Is there any solution in VB.net to reset any entrees made to the Windows system when the USB device is plugged in? Has anyone come across this problem and resolved it via a VB.Net solution?
I have a programme that accepts data from a serial port. If I close the port and then the form no problem. However if I try to close the form with out closing the port it appears to hang. I have tried closing the port in the forms close event but this did not solve the problem.The data recieved event is as below and UseData is the private sub which actually handles the data. Usedata contains the code line Dim InputText As String = SerialPort1.ReadLine Private Sub SerialPort1_DataReceived(ByVal sender As System.Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
Me.Invoke(New myDelegate(AddressOf UseData), New Object() {})
End SubI am aware that this event runs on another thread and I have seen but cannot now find information about closing multiple active threads.or do I have to "uninvoke" the delegate
I tried to make a winsock program.But when i run, i have a SocketException "No connection could be made because the target machine actively refuse it."Any suggestions on what i should do? Im using 17477 port.By the way Im using my own computer to test it. So i have no idea why.How should I open this specific port in my own computer?
Is it possible that I could include it to could into my program so that i don't need to open the ports of each computer? Below is my code.
I'm having this problem with a networked app in vb.net. If the program exits normally the port closes fine, however, if it crashes sometimes it remains open and I am unable to close it. The next time I run the program it is unable to open the port because it is already in use. Here's the exception: 10048: Only one usage of each socket address (protocol/network address/port) is normally permitted on how I can reclaim this port, or how I can close it? I tried using the reuse address socket option
I have ran into a small problem with my code. I got bored lately so I wanted to try a project. A program that will start up with windows starts up and it opens a webpage like google. My code is below.
Imports System.IO Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]....
when a button is clicked, but when I add that code in without clicking a button, it does not work. I have tried to put it everywhere, but it just does not work. I have also looked it up.
I'm trying to open any file using Process.Start, but every time I try to open a file that isn't an executable the program crashes... This is the code I'm currently using:
vb.net Private Sub ListView1_MouseDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ListView1.MouseDoubleClick For Each lvi As ListViewItem In ListView1.SelectedItems Process.Start(path & "" & lvi.Text) Next End Sub
Path is a string that contains the selected folder path, and lvi is the text of the list view item (each item contains the icon and name of each file). It is working fine for .exe files, I was just wondering if it's JUST for .exe files...
I was wondering if its possible for VB to display all available COM ports that are open. he reason that I ask this is because this program will be run on various computers where the COM port will not always be the same. I have a text box now that the user can choose which com number he/she wants but if the wrong one is entered, the program crashes rather than displaying an error message. It would also be nice for the system to show which available com numbers there are
I have things set up so that the program is ready to start logging ,only when Recieving=true.This is controlled with Button1. So I click button1,Serial port is open and waiting for some signals from the Dyno.When 1 signal come it put a "1" in TextBox1 ,and for the second a "2" and so on. Thing is sometimes it starts right away, like I want it to,and sometimes it lags a fraction of a second, even though the Port is open.When it lags there are already 5 to 10 signals gone by before it starts logging 1,2,3,...and so on. Sometimes it don't start at all.Then I have to close and re-open the form and it works,but with lagging on the first "set"
"Textbox1 > 0 then" triggers a timer (not seen in this code)that samples Textbox1 once pre interval and writes the value to a listbox. On the upside as soon as a "1" is displayed in textbox1 the timer starts like it's supposed to.I noticed this behaviour before I added the timer and besides the timer has nothing to do with the signals coming from the SerialPort. I have my form setup so I can run "sets".Run one "set"...save...reset...run another "set" ...and compare.It's always the first "set" thats off.If I run multiple "sets" the first one is completely "whacked", and the rest are consistent.
Think this could be the SerialPort lagging,or code problems?
Public Class Form1
Dim resetValues As Boolean = False Dim RPM As Double
I am trying to open an Access file but so far I am not succeeding. [Code] I receive following error: Cannot start your application. The workgroup information file is missing or opened exclusively by another user. I am sure the file is not open and I tried already to add in the connection string: ;User ID=User and / or Jet OLEDB:System database=C:SYSTEM.MDW; at the and but without result.
