i dont understand what this means. im not using an array as far as i can tell. i am in a vb class and wou. here is my
Public Class frmMain
Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[code].....
I am getting an IndexOutofRange exception when using a datatable. Here is the code: Dim DR As DataRow = DT.Select(String.Format(SelectString, Val1, Val2, Val3, Val4))(0)
The select should find a record to match - I used debug to verify the format string substitutions and there are matching values in a record in the datatable. So how can I determine the value of the index error?
I have a datagridview on a form that is bound to a table in a dataset from another class.I use a data adapter to .Fill a table in that dataset and the grid displays the data fine.Works fine.On my form I have a textbox the user can type in that will will pass a parameter to the storedprocedure used to fill this table. So on startup the textbox will have "%" in it. and then the user can type in "F%" and get everything that starts with an "F"
So when that textbox changes I launch an async refresh (.BeginInvoke) to do my refresh. The table gets populated with the reduced number of records (I check ds.table(0).rows.count and it is correct)
But the datagridview then starts throwing datagridview.dataerror events. "System.IndexOutofRangeException : Index # does not have a value".It looks like the dataset is getting filled correctly and not having any issues, but the datagrid is not liking this update. The index out of range error is so common that I'm not finding what I need through searches.
It is possible to catch an exception and throw a new exception which wraps the first exception as an inner exception: [URL] Also, if I call a function and it throws a certain error, but I catch it, will the calling code's catch handler execute? If so, and it is of a higher exception type, is this not wrapping the exception? eg I can throw exception ex of type IndexOutOfRange, log it but rethrow, catch a higher up exception and do something, or I can throw a new exception and wrap an inner exception like:
View 1 RepliesI was doing my project and came across an error (The I/O operation has been aborted because of either a thread exit or an application request) regarding this
"Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
If closingdown = False Then
received = SerialPort1.ReadTo(vbCr & "R") 'Motion port receiving data. needs a vbCR & "R" is sensor out is an ASCII "R" followed by three characters (which is the distance measured)
End If"
I'm writing a program that's supposed to keep the employees at my work away from doing things they're not supposed to on the computer. So I made a "launcher" window that's only closeable with password. I also disabled task manager. However when I start an application from my launcher window, the launcher window goes over it because of its topmost property.
View 2 RepliesI have this SQL Statement:
de.SqlStatement = "SELECT A.Name, A.Catagory , COUNT(Patient_ID) AS PNO FROM PatientApplyToAssociation P INNER JOIN Association A on A.Association_ID = P.Association_ID WHERE A.Catagory='" & "health" & " '" & "' GROUP BY A.Name '"
[Code]...
Anyone out there who happens to have an exhaustive code snippet for SEH (including all possible exceptions) for VS 2008 or VS 2010 (.NET 3.5 or 4.0) ?
View 10 Replieshere is the exception error System.IndexOutOfRangeException i want a msgbox saying device not detected
View 2 RepliesI have a class library that is referenced by several other class libraries along with the main program. About two weeks back, I made a change to one of the classes in that base library, which is used as an argument for some events. Since that time, I have been testing code. Today, after a couple more tests, I started getting this exception. It is indicating a field is missing, which was renamed in that change about two weeks ago. The exact code that is raising the exception is code that I have run a couple dozen times in the intervening time, and it has always worked.I have tried everything I can think of, including deleting the bin and obj folders of every module that could be in any way related to this issue, such that the whole thing was rebuilt. I have removed the references and re-added them. Nothing worked. Code that has run fine for weeks has decided that it wants a version of an object that has not existed for weeks.
This problem arose immediately after a different problem, so the two might well be related. The other problem was that, while stepping through code, the IDE decided that one of the code pages was different from when it was last loaded. I get that a fair amount, and solving it is fairly routine. It generally means that I am stepping through code in a dll, and inadvertently tried to fix a bug in that code, rather than in the dll itself. Now it no longer matters. I can't get to that code page, nor can I get to anything else in that dll. It is acting like it has sponaneously decided to revert two weeks back in time, and use that source code for debugging, despite any attempt I make to bring it up to modern times.
i keep getting this null reference exception error and i can't figure out what i need to do to fix it. I have this in the form
[Code]...
keep getting this null reference exception error and i can't figure out what i need to do to fix it.I have this in the form
Private Sub cbLookUp_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cbLookUp.Click
Dim webDownload As New Net.WebClient
[code].....
im making a program and it needs to load 95 files on form load.im trying to make it to if the file cant be found that it will give a error instead of a JIT debug thing. i triedadding
HTML
Catch ex As Exception
MsgBox("Error: " & ex.Message)
[code].....
I am getting this warning after I have changed the computer. I just installed framework and visual basic 2010, trying to edit the application that I been working on and one of the main forms is giving me this error.
Warning 1 Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)) 0 0
I developed an app, tested on few computers and all seemed fine. But now, some people suddenly get an error, which I can't repeat on my computers. Part of the exception:
** Exception Text **
System.TypeInitializationException: The type initializer for 'NumoABC.functionsBurtuSummas' threw an exception. ---> System.InvalidOperationException:
The form referred to itself during construction from a default instance, which led to infinite recursion. Within the Form's constructor refer to the form using 'Me.'
at NumoABC.My.MyProject.MyForms.Create__Instance__[T](T Instance) in 17d14f5c-a337-4978-8281-53493378c1071.vb:line 180
at NumoABC.My.MyProject.MyForms.get_MainForm()
[Code] .....
The If Me.Created = False Then is because while the form is loading, some events fire the updatePersonDataHandlers() sub, but I don't want it to happen until form is fully loaded. In the module functionsBurtuSummas line 2
Module functionsBurtuSummas
Private f As MainForm = MainForm
I have many modules who work with the MainForms' controls, so I use a private variable f to refer to the MainForm.
I am trying to search the C: drive for all files with a certain extension. I am using the following code which is working fine, however when it encounters an error the whole process stops rather than continuing with the scan. (running in backgroundworker, hence the invoke)
Private Sub ScanFiles(ByVal rootFolder As String, ByVal fileExtension As String)
'Determine if the current folder contains any sub folders
Dim subFolders() As String = System.IO.Directory.GetDirectories(rootFolder)
[code].....
Im am trying to get two separate applications to communicate with one another via a txt file. The first application writes to a txt file every even second and the second application reads the text file every odd second. The problem is Im getting an exception saying The process cannot access the file FILE_PATH.txt' because it is being used by another process. Not sure if my code is correct or not? Or if there is a better way to do this?
[Code]...
Weird problem, it only happens for one of my clients, and it happens on all 3 of their computers. Their computers are Windows XP.My form has a Windows Media Player control on it, to play a video from the internet. When the form loads, I get an exception "External component has thrown an exception". It happens in the form's designer, in the InitializeComponent procedure, at this line:CType(Me.wmpVideo, System.ComponentModel.ISupportInitialize).EndInit()
It works great on 100 other clients computers, running XP, Vista, or 7, and this is the first person to have this issue. If I take the Windows media player out of the form, it works fine.BTW, those computers have Windows Media Player installed, I already checked.
.i'm having a slight problem with the following function i wrote
Dim bytes As Byte()
bytes = Convert.FromBase64String(Base64String)
However, it returns me System.OutOfMemoryException error when the Base64String contain large
[code]....
[code]Is it necessary to close object when exception occurs? if yes please correct above code i m confused where to close the response object
View 3 RepliesI've got a little problem. I'm trying to choose a background for the program based on Settings, but I'm getting a Null Reference Exception and I don't know what I'm doing wrong. Here's the
[Code]...
I'm getting a design time NullReferenceException on Dim db As Database = DatabaseFactory.CreateDatabase()and I can't figure out what to do about it. Has anyone experienced this problem or know the solution?
View 6 RepliesI have a simple form that when filled out with a case # will return the name of the person that is handling the case. I am getting an error on any machine that does not have VS 2010 installed on it. The error is when ever the user uses the close button (the red X) at the top right of the form the following error is generated:
System.InvalidOperationException: Collection was modified; enumeration operation may not execute.
at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource)
[code].....
I have exactly same problem as guy at [URL] . Quote: I'm using multithread in my application. in each thread, launch a form which has a webbrowser. each browser is controlled by another thread to test some sites. however, sometimes, it has some access violation exception. these exceptions are not beause of cross thread issue since all processing for the browser are using delegate. And the problem is: I can not catch the access violation exception.
View 3 RepliesThe ExcelClass.vb code used to be in a module(Changed it to classes), and I found it online. Unfortunately, I can't find the link .The program is supposed to look through one file (I call it, the donor, cell, or excel throughout the program) and compare the values found in Column C to the values found in column B of another file, called "definitions". If it finds a match, it'll take the abbreviation in definitions and paste it over the value in column B of the donor sheet.The code maybe solid, I think it is, but I can't find out. It crashes with the above error as soon as it comes time to use the getCell function.[code]
View 5 RepliesTo query an excel sheet via SQL, I used to use either:
Dim excelConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + strPath + ";Extended Properties=""Excel 8.0;IMEX=1;HDR=YES;"""
or
Dim excelConnectionString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source= " + strPath + ";Extended Properties=""Excel 12.0;IMEX=1;HDR=YES;"""
Now this worked fine until I installed Office 2010.
Now I get a
Microsoft.Ace.OLEDB.12.0 provider is not registered on this machine
exception.
How can I find out the correct connection string/provider?
I've got a masked text box that throws an invalid cast exception if I try to put anything in the TextChanged event:
Private Sub mtbZVal_TextChanged(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MaskInputRejectedEventArgs) Handles mtbZVal.TextChanged
MsgBox("OK!")
End Sub
Even more oddly, it throws the exception in a completely different part of the program. The masked textbox is on a form that opens when you press a button, and that's the bit that gives the error:
Private Sub cmdAddLoc_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdAddLoc.Click
If frmLocation.ShowDialog() = DialogResult.OK Then
End If
End Sub
win7 64bit, VB express 2010.
I'm working on a project. The main form is a MDI parent, it host a control form. on control form, there is a button. when click it, it will start, say 10, threads.
each thread will open a standard alone form (not mdi). on each form, it has a web browser control. when the form opened, it will start a new thread which makes the web browser control load a url, then depends on the links in that url, it will load another url, and loop for some times. then, the thread stops, and the form closes.
for some reasons, I got this weird exception:
AccessViolationException was unhandled by user code. Attempted to read or write protected memory. This is often an indication that other memory is corrupted.
1) the exception happens randomly, and not always happen. when it happens, it is always some code related with the web browser, i.e.
Not (MDIWebBrowser.ReadyState = WebBrowserReadyState.Complete)
or
MDIWebBrowser.Document.Body.InnerText()
2) I put a try catch in, but, it can not catch this exception. If I just close the exception dialog, sometimes, it keeps running without problems. sometimes, it just pauses the webbrowser control.
so, I did some research. it seems many people had the exact same problem. and it seems the best choice is:
[URL]
I checked all solutions suggested, even manually change the DEP, by using "bcdedit.exe /set {current} nx AlwaysOff"
but, the exception still pops up.
This is the code I use to open a file:
Quote:
Public filecode As String
Public Sub getfile(ByVal filename As String)
Dim objReader As StreamReader
But I keep getting the filenotfound exception.
I replaced the file source with the actual location of the file and got the same error. I also checked the permissions of the application to allow sharing and remove read only properties.
I'm just converting a date to a string but I'm getting this error. It's not listed as one of the normal exceptions to the datetime.tostring method. Googling around, it looks like it's an actual bug where it thinks StartDate is an int--but that's no help to me, as I just need to convert the date.
dim StartDate as nullable(of date)
dim Date1 as string
if not StartDate is nothing then
Date1 = StartDate.tostring("yyyy-mm-dd")
end if