I built a dwonloader program which download a file from the web. I would like to insert an error message that pop up whenever the program fail to download the file and/or when the computer gets disconnected from the internet while the program is downloading the file.
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I have written a application that has a TCP client and server to connect to a PLC. The Client works perfectly but it looks like the server drops out all the time. What happens is when I first start the connection it will update without any problems but after about 1min of no transfer the PLC can no longer send data to the application. Neither system gives an error and the PLC shows that it is transmitting the data but nothing comes through on the application side of things. I have tried to put in heartbeat to see if that would stop the drop out but to no avail.[code]
View 10 RepliesI can't see anything in the method list that lets you know when a connection drops (and since it's constantly checking, it seems that could have been in there, to raise a flag when it can't find the connection anymore...no?). Is there a way to know if the network connection drops? Is there a way to reconnect it? Is it just a matter of turning EnableRaisingEvents() off and back on to re-establish the link to the network share?
View 6 RepliesI am connecting to a data stream that pushes data continuously and when I tried to set up a network stream I just could not connect and kept getting the 'not found' error. I used the httpwebrequest with webrequest.keepalive = true and started to consume the data by reading into a buffer and then appending to a stringbuilder. Once the stringbuilder reaches max size I flush it to a text file. The problem is that I get disconnected from the data stream because I am not reading the data fast enough. I need to keep the connection open and read the data while ensuring data gets stored in text files. If I use method "CONNECT" it does not connect to the stream.
While (True)
webrequest = DirectCast(Net.WebRequest.Create(url), HttpWebRequest)
webrequest.Credentials = New System.Net.NetworkCredential(username, password)
webrequest.Method = "GET"
[code]....
should I increase the buffer size and if so what is the max? that would mean I can read more data at a time and keep up with incoming push. Disparate here.
ACtually also I noticed that it gets stuck on this line
numbytesread = responseStream.Read(bufferread, 0, BUFFER_SIZE)
and then eventually I get disconnected.
I am connecting to a data stream that pushes data continuously and when I tried to set up a network stream I just could not connect and kept getting the 'not found' error. I used the httpwebrequest with webrequest.keepalive = true and started to consume the data by reading into a buffer and then appending to a stringbuilder. Once the stringbuilder reaches max size I flush it to a text file. The problem is that I get disconnected from the data stream because I am not reading the data fast enough. I need to keep the connection open and read the data while ensuring data gets stored in text files.If I use method "CONNECT" it does not connect to the stream.[code]
View 1 RepliesAll 3 statements below do NOT download the file; BUT also do not create any error msgs! owever, when pluggingFTP://localhost/QMSpathFTP/Prozess Akquisition.doc directly into the IE the .doc is shown correctly! I.e., to me, the virtual directory 'QMSpathFTP' is correct!
View 2 RepliesI am totally into structures at this point, mostly because of their simplicity in use. I am now working on a "download structure", which allows you to download and keep track on a file.This is the
Public Structure FileDownload
Sub New(ByVal URL As String, ByVal DestFilePath As String)
Me.URL = URL
[code].....
I have the RTM version installed. I am quite puzzled at this wizard. It works fine with SqlClient. But for Access databases, this wizard completely fails.In this wizard, I only have one option to do - setting the ConnectionString. [code]
View 1 RepliesI've came across a little problem with my tcp / ip server. My client can connect to it with 127.0.0.1 ( localhost ), and 192.168.0.X, but every remote connection fails to connect.
Here's the connection rituals:
Server
listener = New System.Net.Sockets.TcpListener(System.Net.IPAddress.Any, Port)
listener.Start()
listenThread = New System.Threading.Thread(AddressOf doListen)
listenThread.IsBackground = True
listenThread.Start()
Client
client = New System.Net.Sockets.TcpClient(IP, Port)
client.GetStream.BeginRead(readBuffer, 0, BYTES_TO_READ, AddressOf DoRead, Nothing)
I would really welcome some help with this issue. We have a php code that works and connects to the LDAP. When I try to connect using VB.NET 2010, it fails to bind with logon failure unknown username or bad password. Below is the connection information. When I talk to the folks who run the ldap server, they say I am binding sucessfully, below is the log file for the sucessful bind? If I continue and try to execute a search I don't get any results. The server is running openLDAP ver 2.3.39 on a linux server, server requires connection on port 636 for secure connection, or 389 for anonymous.
[Code]...
I have made a small form where I have bound textbox with records from database.Although my code for inserting and updating the record seems fine and working. But when I view the database, tables i see no inserts/updates made there. But When I run my application again, I see the records in the bound textbox but only for some seconds (for around 1 and half minutes), although they are not shown in the database (tables) actually.
When I close the application and run again it after 1-2 minutes there are no more records bound to the textbox, since no records at all.How can this be possible. I don't have any idea what's going on.
I have been using visual studio 2008 and sql server.Code I have been using for ::
'Update the Records Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
[Code]...
im trying to write to an sql database. im inserting an image, as well as some other information. I am using the following code which works fine, as long as i do not add an extra column/variable "LOCATION" in to the mix and leave "
'Cmd.Parameters.Add("@LOCATION", OleDb.OleDbType., 3).Value = "testing"
commented out. *this is undesireable as im trying to add extra criteria to be saved like LOCATION.
Try
Dim st As New FileStream("\serverfolder1storage" & "pdftemplate.jpg", FileMode.Open, FileAccess.Read)
Dim mbr As BinaryReader = New BinaryReader(st)
Dim buffer(st.Length) As Byte
[code]....
i am trying to store the location e.g "c:file1.jpg" in the sql db. Can anyone reccomend a solution to this using OLEDB? ideally i need to add approx 4 more variables. e,g
firstname
surname
dob
location
I am trying to save a new object to the database using petapoco.I have an object that uses a Guid for the primary key.Here is an example of the objects primary key property.
<PetaPoco.Column()> _
Public ReadOnly Property Primkey() As Guid Implements IStandardDocument.Primkey
Get
[code]....
Here is an example of the save method.
database.Save("Reservations", "Primkey", reservation)
The sql that is generated is an update with a primkey of 00000000-0000-0000-0000-000000000000 instead of an insert. So new records are never inserted.If I have an existing object with a valid guid the update and delete all work correctly.
I am trying to download a file from my VB.net application.
View 4 Repliesi have made many updaters and download managers however i have never worked out how to make it so that the if th connection is lost that it will jsut wait for a new connection and continue with the download. anyone know how to do this?
View 2 Repliesi have an application. which is executed after every 5 mins. i have an open connection but it gives me the following error:
ExecuteScalar requires an open and available Connection. The connection's current state is closed.
my code is something like this. I have shown where all i am using ExceuteScalar()
Sub Main()
Try
connection.open()
cmd.ExecuteScalar()
[code]....
I have a simple scraper. It works on some websites, but on some there is this Error:
Quote:
IOException was unhandled Unable to read data from the transport connection: The connection was closed
It is occuring at "Dim htmlresults As String = Urlcontents.ReadToEnd()".
'Create the HttpWebRequest object
Dim req As HttpWebRequest = WebRequest.Create(URL)
'Set the timeout to 1 second (or 1,000 milliseconds)
req.Timeout = 10000
[code]....
I have a function that will get the present upload and download rate of my current connection.
It is working now here is my code used:
Dim NetSent As New System.Diagnostics.PerformanceCounter
Dim NetReceived As New System.Diagnostics.PerformanceCounter
Dim KBytesSent As Long
Dim KBytesReceived As Long
Do Until Me._Stop
[Code]...
I cannot subclass a window form some reason (running as administrator) Is there something I missed here:
vb.net
Public Delegate Function WndProc( _
ByVal hWnd As IntPtr, _
[Code].....
This will happen at random, and I can always just catch the error and re-establish connection to the server, but I am confused as to why. When doing lots of inserting into the sql server, I only establish one connection that is public, instead of many little connections. I had my doubts on a public sql connection, but it's been running great, and I've seen no problems until this morning. Again, this random moment I hit an error that stated, sql connection state is broken. Is it bad practice to just accept this error, and when it happens, re-establish the connection?
View 7 RepliesIm getting an error with my insert statment "Syntax Error in INSERT INTO statement". I do not understand why. Im using global variables from form 1 and using them in form2 and trying to insert them from form2 into the database.
[Code]...
I have this app written in VB.Net with winforms that shows some stats and pictures on a bigscreen monitor.I also monitor the memory usage of sad app by using this. Process.WorkingSet64
I know windows does not always report the correct usage but I just wanted to know if I didn't have any little memory leaks which I had but are solved now. But the first week the memory usage was around 100MB and the second week the memory usage showed around 50MB.
So why did it all of a sudden drop while still running the exact same code?I can hardly imagine that the garbage collector kicked in this late since the app refreshes every 10 seconds and it has ample time in between those periods to do it's thing.Or perhaps there is just better way to get memory usage for a process that is more reliable.
I'm having problem regarding session items. Before I use them, I want to check if they exists, but using this codes gives me error:[code]I think Session("SomeSessionItem") tries to acquire the value of the session item. If the item doesn't exists then it throws exception. But how do I check if a session item exists before using them? I have a page Home.aspx.In the Home.aspx.vb, I instantiate a WebUserControl SomeControl.ascx. Note that in Home.aspx.vb event handler Page_Load I can use a condition to check session without getting an exception.Inside SomeControl.ascx.vb I'm trying to access the session, here's where the exception occurs.
View 5 RepliesMy application is connecting to a webservice but when the webservice is offline, it will show a messagebox saying there has occured an error in my application. Giving me the option to send a report...I surrounded my whole code with a try catch to catch unsuspected errors. But still this window appears. How can I stop this?
View 5 RepliesI've been using some code which I found on the net, and have noticed that the first byte is never recieved. Annoyingly, this contains the MAC addresses, which is the bit I want. Below is the relevant snippits:
Public Sub [Start]()
If m_Socket Is Nothing Then
Try
[Code].....
I have 3 lists in my form.When 1 list is clicked, I want to drop the selection in the other 2 lists.
Private Sub lstPlaylist_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstPlaylist.SelectedIndexChanged
lstArtist.ClearSelected()[code]....
This is my current code. When I click on lstPlaylist, it drops the selection for all lists.
I have a program that sends some data on a networkstream through a tcp connection.
[Code]...
I verified data types that are being inserted to insure that this is my problem. I dont see any exception errors.Am i missing a veriable or something that is related to my connection.
Imports System.Reflection
Imports System.Data.SqlClient
Imports PSXSTL.Data.DataAccess
[code].....
I'm trying to insert variables into my connection string hoping that they will be saved for executing multiple queries.
What I'm trying is something like this:
Private sConnectionString As String = "Provider=TDOLEDB;Data Source=TDDEV;Persist Security Info=True;User ID="&user&";Password="&pass&";Default Database=bcpm_ddbo;Session Mode=ANSI;"
[Code].....
In the form load event, I connect to the SQL Server database:
Private Sub AddBook_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
myConnection = New SqlConnection("server=.SQLEXPRESS;uid=sa;pwd=123;database=CIEDC")
[code].....
