Error: COM Object That Has Been Separated From Its Underlying RCW Cannot Be Used
Dec 13, 2011
I'm designing an ATM where I have to allow a user to "insert" his card and then conduct transactions. After the first user is done, without closing the application, another user should be able to use the ATM. However, whenever I try to log the second user in, I get the following error: COM object that has been separated from its underlying RCW cannot be used.
My code for the opening screen is as follows:
Imports System.Data.OleDb
Public Class StartScreen
'Form-wide variables
[code]....
View 3 Replies
ADVERTISEMENT
Jan 5, 2010
I have a program that opens a FormReportViewer. I get an error when I close my program...COM object that has been separated from its underlying RCW cannot be used.
View 2 Replies
May 10, 2011
I've written a custom class MyClass and marked it with the <Serializable()> attribute. I have a set of binary files on my hard drive that I've serialized using BinaryFormatter that came from instances of MyClass.
I've recently changed the structure of MyClass slightly (added some properties, deleted some properties, changed a few methods, etc).
What happens when I try to deserialize the existing objects to this changed class using the code below? I've tried it and not had an error thrown or anything - but surely it can't deserialize properly when the class has changed? Is there a way I can get some useful information out of the serialized files even though I've updated the class?
Here's the code I'm using to do the serialization:
Public Sub serializeObject(ByVal obj As Object, ByVal outFilename As String)
Dim fStream As FileStream
Try
[Code]....
View 4 Replies
Nov 15, 2011
I have the following code that I'm trying to retrieve the HTML document. Not sure why it wouldn't work. Here's what I captured from Live HTTP Headers:
[Code]...
View 2 Replies
Jun 4, 2012
When I call the restful service with the following code, I am getting the error
[Code]...
View 1 Replies
Dec 4, 2008
I'm creating a program (Which will eventually be a service) which loops a section of code which downloads files from a variety of FTP servers.All files are succesfully downloaded on the first iteration, however after this the download fails with the following error..."The underlying connection was closed: An unexpected error occurred on a receive."Curiously, the error does not occur if the loop only downloads the same file from the same Ftp server. It only occurs when 2 or more files are downloaded.I use the following code...
Dim fwr As FtpWebRequest = CType(FtpWebRequest.Create(Supplier.FTP_Address & Supplier.FilePath & Supplier.FromFile), FtpWebRequest)
'Set credentials
fwr.Credentials = New NetworkCredential(Supplier.Username, Supplier.Password)
[code]....
View 4 Replies
Jun 1, 2010
I have got a code snippet as follows:
Dim fstream = new filestream(some file here)
dim bwriter = new binarywriter(fstream)
while not end of file
read from source file
bwriter.write()
bwriter.flush()
end while
The question I have is the following. When I call bwriter.flush() does it also flush the fstream object? Or should I have to explicitly call fstream.flush() such as given in the following example:
[Code]...
A few people suggested that I need to call fstream.flush() explicitly to make sure that the data is written to the disk (or the device). However, my testing shows that the data is written to the disk as soon as I call flush() method on the bwriter object.
View 1 Replies
Apr 30, 2009
WTF, here's my code...
Public Class Form1
Dim BIT01 As Integer = BIT_01.Text
Dim Value As Integer = TB_OutPut.Text
[code].....
View 1 Replies
Oct 6, 2009
I have a windows service I created that checks for data to post to an off site webservice over SSL. The service checks every 10 seconds for data to send, if there is data it opens a connection to the remote webservice, and closes the connection after 120 seconds (still checking for data to send during this time). The service works fine if a user is RDP'd into the server, but as soon as no one is logged on and the service attempts to push data, I receive the following error:"The underlying connection was closed: An unexpected error occurred on a send."I have tried running the service as a local service, network service, under my login, and under a service account, but nothing seems to work. The PC it is running on is a windows 2003 server (virtualized - vmware)
Protected Overrides Function GetWebRequest(ByVal Uri As Uri) As System.Net.WebRequest Dim oWebrequest As System.Net.HttpWebRequest = MyBase.GetWebRequest(Uri) oWebrequest.KeepAlive = False oWebrequest.ConnectionGroupName = Guid.NewGuid.ToString oWebrequest.ProtocolVersion =
[code]....
View 1 Replies
Oct 16, 2009
Say I have a List(Of Tag) with Tag being an object. One member of Tag, Tag.Description, is a string, and I want to make a comma-separated concatenation of the Description members.Is there an easier way to do this than to read the Description members into a List(Of String) and then use the Join function?
View 2 Replies
Jul 11, 2011
I have a string like
human, roti, makan, ghar, house, language, english, india, US, master, teacher, html, code, asp, jsp
i need code for find the input string.
View 3 Replies
Jan 12, 2010
i am using VB.net 2003 and i am trying to get the number of rows of a dataset from form1 into form2 in order to use it for something else and i am getting the error"System.NullReferenceException occured...Additional information: object reference not set to an instance of an object"...my code is like this:in form1:Public x as integer= me.dataset.table.rows.count here it gives me the error
in form2:
dim frm as new form1
msgbox(frm.x)
View 1 Replies
Jan 5, 2010
I am getting this error when I try to print my report. Here is my print code.
Private Sub PrintToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PrintToolStripMenuItem.Click
Dim Print_Dialog As New PrintDialog
[code].....
Here is my error: System.NullReference Exception: Object reference not set to an instance of an object.
View 1 Replies
Aug 14, 2010
with datagridview1
while looping through all the cells
i am trying to allot a cell value to another cell value basing on some conditions
& finally delete one column.my code is as fallows
Dim i, x As Integer
i = 0
x = Me.DataGridView1.Rows.Count[code]....
error i am getting is : Object reference not set to an instance of an object.it is extremely surprising for me the same code has worked nice for me but why & how the same line of code is generating this error.
View 10 Replies
Mar 14, 2010
The issue is when I try to add a new item to the ArrayList with the following code, it gives me an error:
vb Private Sub btnLabelAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLabelAdd.Click
Dim result As String = InputBox("New Filter Label:", "Label List")
[CODE]................
Object reference not set to an instance of an object.
I'm not really sure what I'm supposed to be doing with this. It's a new setting I just added and it's empty, so I'm not sure if that has anything to do with it or not. Anyone know what's going on and what needs to be done to get it to accept a value and not want to be "initialized"?
View 9 Replies
Oct 23, 2009
I have recently gotten my hands on a free, open-source IMAP connection API.So far, I have been successful in creating a connection to one of my accounts.Where I'm getting stuck is retrieving folders and/or emails from those folders.Does there happen to be anyone here that is familiar with this API, or even Gmail (particularly the folder structure for IMAP)?
If not, here is a link to the DLL that is listed on sourceforge and the company's website that created it (if you feel like testing):
Koolwired
Sourceforge - Koolwired API
I have created a test account so feel free to use the code below without worrying about username/password issues; I'll just delete it when I'm done with it.Here is the code I have made so far for making a connection:
Dim gSession As New Koolwired.Imap.ImapConnect("imap.gmail.com", 993, True)
Dim gAuthenticate As New Koolwired.Imap.ImapAuthenticate(gSession, "imap_test@serysoft.com", "imap_test")
Try
[code]....
When I run that code, I get an error that states:System.NullReferenceException: Object reference not sent to an instance of an object. (The bold line in the above code).
Now, I'm not sure exactly what that means. Does that mean it tried to access the server and "INBOX" doesn't exist so it gets returned a NULL value? Or is it possibly the coding itself?Maybe the Gmail folder system is weird due to the fact they use labels (even though from what I have read online, the labels act as the folders in the IMAP system).
View 11 Replies
Apr 18, 2010
I got the following code from the demo code samples and just changed the textbox names. But it throws an error:
Private Sub Fill_TextBox()
Dim Num As Integer
Dim DSet As DataSet
[code]....
The error is:
System.NullReferenceException:Object reference not set to an instance of an object.
View 1 Replies
Mar 4, 2010
Here is the code for the button click event;
Protected Sub CompetenciesButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles CompetenciesButton.Click
Dim con As String = WebConfigurationManager.ConnectionStrings("foo").ToString()
[code].....
View 1 Replies
Oct 30, 2011
I am completely new to ASP.NET and VB as well as C#. I am trying to add customers to a contact list out of a DB. Then the list can be referenced to call them up. But when I try to run it I get System.NullReferenceException: Object reference not set to an instance of an object. In line 19.
Here is my code:Page 1 is default page...it connects to the database and grabs the contact information and allows me to select the current contact and add them to a listbox on a separate page:
Imports System.Data
Partial Class _Default
Inherits System.Web.UI.Page
[code]....
The error occurs on line 19 (For Each customerEntry As DictionaryEntry In Customer) in the second set of code from the default2 class.
View 1 Replies
May 2, 2010
I am making an application that takes information from the textboxes and saves it to a sequential access file or text file named checkfile.txt. I have the textfile in the proper location within the project folder.
I am getting an error stating Object reference not set to an instance of an object.
And this part of the code is highlighted
CODE:
Here's the code:
CODE:
Attached image(s)
View 6 Replies
Jul 28, 2011
I am taking some code that I have used for a nested listview before and trying to make it work with a nested Repeater but I am getting an error.
System.NullReferenceException: Object reference not set to an instance of an object.
.aspx
<asp:Repeater ID="reMainNav" runat="server">
<HeaderTemplate><ul></HeaderTemplate>[code].....
View 1 Replies
Apr 13, 2012
I'm having this problem with my code and cannot seem to get past it although it was working fine before. The error is "An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object." The code is:
CODE:
I am trying to get information to be pulled out of a database and show in text boxes on another form (frmviewsdets). The error occurs when it gets to the line frmviewsdets.txtsnumber.Text = rdr("StudentNumber") and even when a breakpoint is applied there it just moves on to the next and so on.
I have tried to show frmviewsdets before I pull the data out of the database beut I get the same message.
View 14 Replies
Apr 15, 2009
I'm finishing up working on the high score list of my Jeopardy game. The only problem that I'm running into is when I try to start from scratch without a textfile in the Debug folder.I get a NullReferenceException was unhandled - Object reference not set to an instance of an object. I get this message with the line If (myPlayers.Length - 1) > 2 Then just before I start to compare the scores and reorder the list by score if necessary.I already declared myPlayers as an array of structures in the beginning of the form.
Private myPlayers() As Players
It writes the name and score to the file, but then gives me that error. My goal is to only fill the file with the three players names and their scores.I figured since the file doesn't exist, I'm doing something in that specific code that effects my reference to myPlayers but I can't figure out what exactly. I tried adding
If (myPlayers.Length - 1) > 2 AND File.Exists("highScore.txt") Then
but its still giving me the error.
'read in scores, add scores to file or create new file if neccessary
If File.Exists("highScore.txt") Then
Dim InputFile As StreamReader
[code]....
View 5 Replies
Feb 22, 2012
I have
Public stack() As CTest
I want
Public stack() As Object
The latter is giving the error "Unable to cast object of type 'Object' to 'CTest'." when used:
Dim thestack As CTest() = testdatabase.getStack
Where testdatabase.getStack simply returns stack();
Public Function getStack() As Object()
Return stack
End Function
This fixes it, but it's not ideal (for me personally):
Dim thestack As Object() = testdatabase.getStack
So if I could keep the variable as-is (Public stack() As Object) and then do something along the lines of class.stack() = CTest I should be able to do Dim thestack As CTest() = testdatabase.getStack because the object array will programmatically have changed from Object to CTest.
View 1 Replies
Aug 12, 2011
I am coding in vb.net. At times the data is empty/null this is due to user's input into the db.i will like to bypass it, however i get no luck.here is snippet of my code:
If hct.mydbvalue.name IsNot Nothing Then
dr("mydbvalue") = hct.mydbvalue.name
End If
I still get an error: System.NullReferenceException: Object reference not set to an instance of an object.is there a way if it is a null value to not do anything?
View 10 Replies
Feb 7, 2011
When the following executes, I get the error 'NullReference Exception' - Object reference not set to an instance of an object. TestClass has Get and Set methods for the integer property TestWord.How should the following be changed to let me set TestWord in six elements of TArr?
Dim TArr(5) As TestClass
For i As Integer = 0 To 5
TArr(i).TestWord = i * 10
Next
View 1 Replies
Jul 9, 2009
I'm currently building this website which consist of a few webpages.
1.) Login Page
2.) Menu Page
3.) Add Application Page
4.) Search Application Page
My login is working fine, but occasionally when I start to run and debug the prog, it will stop running and point to this error. This is my login page
Partial Class Admin
Inherits System.Web.UI.MasterPage
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim ans As String = Session("Status").ToString()
[code]....
View 1 Replies
Apr 7, 2011
I am using VS2008 and vb.net.I have a nested tabcontrol.
tabControl 1 and tabControl3
In tabControl3 I am trying to populate a text control with a value from a control placed on tabControl1.
' add a savings tabpage
Dim strSavingsPage As String
Dim dblTaxRate As Double
[code]....
The complete error is: NullReference exception was unhandled Object reference not set to an instance of an object.
View 6 Replies
Oct 22, 2010
Am trying to debug an application written by someone else. The issue is we get an "Out of Memory" when executing the following code
[Code]...
View 1 Replies
Sep 25, 2011
I have this visual basic error and i was wondering if anyone could help.Private Sub SearchToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SearchToolStripMenuItem.Click
[Code]...
View 3 Replies
