I Receive Many UDP Connection From None IP Valid Devices With This Code:
receivingUdpClient = New System.Net.Sockets.UdpClient(Port)
Dim byteBuffer As [Byte]() = receivingUdpClient.Receive(RemoteIpEndPoint)
Now I Want Response Data To Device After Receive Data. I use This Code
receivingUdpClient.Send(receiveBytes, 10)
But Received This Error :
"The operation is not allowed on non-connected sockets."
I'm dabbling with writing a client/server app using sockets, for the first time. I've found some example code for a chat application which gives me some pointers, and I've got that working, but now I am trying to refactor the basic code (the example is all in embedded in forms) into classes but I'm running into difficulties. Basically I want a server application to listen for inbound messages with a general Listener object which will parse the message (which will include a reference so I can work out the address of the computer sending the message).
When a request comes in from a new computer it will create a new object containing (amongst other things) a new TCP connection back to the client for managing and returning messages.The problem is I'm getting the message "The operation is not allowed on non-connected sockets" in my refactored code.The original code (on a form with a single listbox and a background worker) looks liks this :
Imports System.Text
Imports System.Net.Sockets
Public Class Server
[code]....
I get the error on last line of code of the OnConnect procedure when my client application tries to connect. Now I know this worked fine with the original code but my new version of the code fails to set up the connection. I have removed the "background worker" stuff because as far as I can tell all it is doing is updating the display which I don't need to do.
I am trying to find out if the connection of my sockets (TCPClient) is connected or not connected. I am using the following code:
[Code]...
I am getting an error "Operation is not allowed while object is closed". On this line of code "Do While myRecSet.EOF = False" here is all my code. First the module/function
Code:
Module Module1
Public coater As String
Public myQuery As String
Public myRecSet As New ADODB.Recordset
Public Conn As ADODB.Connection
[Code] .....
is the insert of my code to close a form and it happens to be that when i click on the close button it gives the error "Operation is not allowed when the object is closed"and highlights the adoPrimaryRS.Close() line.
View 7 RepliesI am using an ADODB connection to a Sybase ASE Database for a small app that runs queries and returns the results to a grid, to XML and to Schema file. I recently tried the query on a Sybase script (Between a Begin and End statement) and had an exception when I used RS.EOF which reported "Operation is not allowed when the object is closed." The code works fine for other queries, including those between begin and end statements, so I did some debugging and found that the failure only happens when my SQL script (Which is typed into a rich text box) contains either Sybase variables (ex. @MyTable) or uses temp tables (ex. Select * into #mytemptable from myrealtable). The actual execution works OK (without an exception) but the recordset seems to be closed. A failing example is :
Begin
Declare @Name Varchar(30)
Select @Name = "MY_TABLE"
[Code]....
Im trying to take fields from a Products Table and populate a listbox in a userform with the productName field. that works fine. but i also have to open the recordset and the connection. when i run the program, i get an error saying the 'operation is not allowed when the object is open' then it highlghts the bolded line in the following code:
Sub testc()
Dim SQL As String
SQL = "SELECT ProductID, ProductName, RetailPrice, QuantityOnHand " _
[Code]....
how can i get rid of the error? and what is the problem? i've tried closing the recordset in various places in different subs but nothing works. .
I'm having difficulty using this code that the tutor has provided for me and have a strange error that only I appear to have. Below is a picture and my code... I have double checked my connection and reference and it all seems to be working fine. Whenever I click on a button within my application when i compile it the error below occurs.[code]...
View 1 RepliesEssentially every time I run my form it tells me that the operation is not allowed when the object is closed and it points towards my recordset. Below is my code in full (given to me by a teacher! not my own) and I wondered if you could tell me what the problem is. As I understand it there is another option to ADODB which is more appropriate for .net.
Code:
Option Compare Text
Public Class Form1
Private m_cnADOConnection As New ADODB.Connection
[Code]....
i have this error when executing "Operation is not allowed when the object is closed" on line rs = cn.Execute(Query)
this is my
Do
tsReadLine = tsR.ReadLine
If Len(tsReadLine) = 0 Then GoTo skip_line
[Code]....
I'm very beginner in vb. I need to connect two forms with ms access. First form is connect with second using(form2.show). My need is when I execute the coding. I got a error on first form " An error occurred creating the form. See Exception.InnerException for details. The error is: Operation is not allowed when the object is closed.
View 2 RepliesWhen I try to run my DLL in Autocad, I got the message below.Application attempted to perform an operation not allowed by the security policy. To grant this application the required permission, contact your.I know there are many threads on this error, but Im not sure about one thing.Can I resolved this on our FilesServer or I have to do something on each computers that will use the DLL ?
View 3 RepliesThis error occurs when I want to add my app to the startup keys
My.Computer.Registry.LocalMachine.OpenSubKey("SOFTWAREMicrosoftWindowsCurrentVersionRun", True).SetValue(Application.ProductName, app)
[code].....
I searched, I found another post, but didn't quite understand the answer... Here is what I am working with.I know the connection is good it does update it by 10 then give me the error...
I am using Visual Basic 6
Code:
Private Sub Form_Load()
Dim sql As String
sql = "select * from Stats ORDER BY Hours"
With ADO
[Code]...
I need to make sure that the connection to a POS printer is successful before writing data to the database and then printing a receipt. The POSprinter is normally of type BTP 2002NP but may differ. The common thing is that they are all connected via COM-port and NOT usb, so no drivers installed at all on the client. Can I send some kind of "ping" on a COM-port and check if a device is connected and turned on? Additional information, the application is developed in VB.net and Visual Studio 2008
View 2 RepliesI am Using Visual Basic 2010. I want to check My Connection Status. Connected or not in Remote Server Connection (SQL Server 2008 R2). How To Check Connection Status..?
View 1 RepliesI've searched the forums but never seems to find an answer for this one.. I recently connected to MySQL database server "Automatically" in Visual Studio 2010. I want to know if there's a way to determine the connection state for "Automatically created" connections in Visual Studio 2010. I know how to do it for"programmatically created" connections but just want to know how on the auto-generated ones.
View 1 RepliesI'm trying to connect a remote mysql database. I'm doing it from a vb.net 2005 application with a connector mysql.data.dll What's happening is, suppose if I try to connect thrice it connects twice and once throwing an exception that says A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. there's nothing wrong with the code, otherwise it would never have connected
View 4 RepliesI have this as my transactions code and I'm having an error connection closed . Iv tried fixing it with odb.open but i dont know where should I put it
[Code]...
Dim Conn As New ADODB.Connection
Dim rs As New ADODB.Recordset
Conn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & "C:Documents and SettingsUserDesktopContribucionescontribuciones.mdb"
rs.Open()
rs.Open("SELECT * FROM master")
rs.MoveFirst()
TextBox1.Text = rs.Fields("sueldoanual").Value
I have this error
The connection cannot be used to perform this operation. It is either closed or invalid in this context.
On my program I am trying to make a ToolStripStatusLabel's text change to "connected" if connected to a network and if not connected to a network change the text to " Not Connected" then I don't know how to display a image if connected to a network or not connected. So if the computer is connected to a network I have a image that I would like to be displayed next to the ToolStripStatusLabel. And if not connected to a network, can the program display a different image? I tried this:
My.Computer.Network.IsAvailable=True(ToolStripStatusLabel2.Text "Connected")
My.Computer.Network.IsAvailable=False(ToolStripStatusLabel2.Text "Not Connected")
I get this error on the server. I cannot replicate this on my development machine.I get it when i call ExecuteReader, ExecuteScalar or when i try to fill a dataset.I use an oracle database.This, i think, increases when the load on the server increases. Im not sure.i need help fixing this. Please let me know if you need anymore details.The code for ExecuteScalar would be as follows
Public Function ExecuteScalar1(ByVal sExecuteString As String, ByVal sConnectString As String) As String
Dim OrclCmd As New OracleCommand
[code].....
I'm trying to convert code from Delphi to .Net. I'm stuck on one line:
//Delphi code ss := Copy(ss, Length(ss), 1) + Copy(ss, 1,Length(ss) - 1); 'vb.net code ss = ss.Substring(0, ss.Length - 1) + ss.Substring(1, ss.Length - 1)
Delphi combines the two substrings, while .Net just concatenate them like a copy.
I have a problem when trying to send a POST request. The sending method looks like this:
Public Sub SendXML(ByVal file As String)
Dim reader As New StreamReader(file)
Dim data As String = reader.ReadToEnd()
[Code]....
Now looking at this I suspected that it was due to the fact that the server does not accept POST messages. But some other reading suggests that the the URI [URL] has been generated with a proxy and should be /Request so the line should read POST /Request HTTP/1.1
So what would be the common reason for this? And if it is a proxy problem, how is it sorted?
As asked below, I have created a new question for the more specific request. Changing absolute URI to relative in HTTP POST header
I know that you cannot specify a constructor in an interface in .Net, but why can we not?
It would be really useful for my current project to be able to specify that an 'engine' must be passed in with the constructor, but as I cant, I have to suffice with an XML comment on the class.
are nested functions allowed in visual basic?
View 9 Repliesi am currently having two problems with this assignment. The program allows the user to add new students to a listbox with a unique Id, lastname and test average. When adding a new student to the listbox, part of the assignment is to not have duplicate students added. I am currently stuck at trying to figure that out. I have figured out how not to have duplicate courses under the course information form but when trying similar code for adding a student i cant get anything i try to work. the next problem is when searching for a student from the list and clicking on the Course Information button, the course information added for that student needs to be displayed. My problem is getting the student searched information to show up right, but if i add three students and search for the first one i added and click on course information button it only shows the last student i added. this is my code for the whole program
Public Class Form1
Private allStudent As New List(Of Student)
Private currStudent As Student
[Code].....
I got this Error : Reference to class 'ApplicationClass' is not allowed when its assembly is linked using No-PIA mode.
This Is My Code:
Imports System
Imports System.Collections.Generic
Imports System.Drawing
Imports System.Reflection
Imports System.Threading
[Code] .....
When I installed Visual basic 2008 express edition it seemed to work, but when i was going to make a project it pups up a error box and it says: Regestry it not allowed.
View 2 RepliesI'm trying to declare name of the string to be same value as that string.For example:
Dim x As String = x
Quote:
Originally Posted by ERROR MSG
[code].....