VS 2005 Invocation Exception Using AutoResetEvent?
May 16, 2009
I am using a background worker to process some login information. However, the background worker has to stop and wait for 2 events to happen. Once these have finished the background worker can complete its job. They are callback that will call the Set() method of the AutoResetEvent.
So I am using AutoResetEvent to set when these 2 events have finished. However, I seemed to be getting this error message
"Exception has been thrown by the target of an invocation." and Inner exception
"Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index". The exception usually fires when the registration success leaves scope.
The code for the background worker.
' Waiting for 'Account in use' and 'Register success or failure'
Private loginWaitEvents() As AutoResetEvent = { New AutoResetEvent(False), New AutoResetEvent(False) }
When a delegate method throws an unhandled exception, that exception is usually trapped at the level of invocation (eg. Delegate.Invoke()) - you get a System.Reflection.TargetInvocationException...
However, when debugging classes utilizing a lot of threading/invoation, it would be helpful to be able trap the exception in the target method i.e. the faulty code, and since Microsofts BackgroundWorker (exceptions thrown in DoWork()) is able to do it, why can't I???
I'm working on an application that contains a "BackgroundWorker", the "BackgroundWorker" worked fine but after I started to change some stuff it gives me an error ("Exception has been thrown by the target of an invocation.")... I used a breakpoint to see where it happens, the exception gets thrown at the "End Sub" line of the BackgroundWorker.I then deleted all the code inside of it and ran it again.I still get the error.
What is the meaning of this error message? "Exception has been thrown by the target of an invocation"
Instead of words, here is my code's logic : while loop run BGworker01 run BGworker02 ... run BGworker09 application.doEvents thread.sleep(10) end while
All the bgWorkers do the same thing (sending some data, only to different locations). When I run this loop with only 1 Background-Worker, it's all fine, but when I add the other bgWorkers i get the mentioned error at the "application.doEvents" part of the loop. I think it also points to another place (highlighted in green) inside one of the bgworker's code : Dim FileStreamToSend As FileStream = New FileStream(fileToSend, FileMode.Open) I thought it might be a problem that all bgWorkers are trying to read from the same file together, but when I tried using different file for each bgWorker, the problem persisted.
I know this is a relatively common error but I am working in an application that allows custom reports to be written using vb.net or C# for scripting. Error handling is very poor and I am not knowledgable enough to add my own (if it is even possible).
My code simply retrieves a value that is stored in a textbox on the report formatted as LastName, FirstName and truncates all characters after the comma. This value LastName is placed in a new textbox on the report. Here is my code:
Sub Detail1_Format Dim lastNameFirstName As String = "" Dim lastName As String = ""
[Code]....
The error happens when I use lastNameCommaIndex to set the number of characters in my substring. If I replace it with a number the report is published properly.
I have a winform where I have some controls like TabPane, Label, ....When I launch my application without localization, it works fine. When I put localizable parameter True, I have this error :
TargetInvocationException was unhandled
Exception has been thrown by the target of an invocation.And when I debug my application, I follow the execution, program begins executing InitiliazeComponent(). I press F11 to continue the debug, program executes the TabIndex event of my TabPane and on the first instruction it crashes.My environment is VS2008, Framework 3.5. I store my project on a network hardisk (I test on local and it doesn't work too)
I am creating a programming that is sending info for one pc to another over RF. The desktop show create a xml file. It writes some of the info but not all. I receive a Target Invocation Exception Error. I realize I need to slow down the incoming Data. I want to use a timer to slow it down.
It errors often (not in a system damaging way) but enough that it bothers me.
Code
Public Shared Sub Fire(ByVal thisEvent As [Delegate], _ ByVal ParamArray args() As Object)
[code]....
Common Error
User Message: Async event fire error. Error Type: System.Reflection.TargetInvocationException Error Message: Exception has been thrown by the target of an invocation.
I have a vb6 app, the error from event view is Faulting application vb6.exe, version 6.0.81.76, stamp 3592011f, faulting module vba6.dll, version 6.0.0.8169, stamp 358b0c74, debug? 0, fault address 0x0001982e. For more information, see Help and Support Center at [URL] And a message box pop out. Exception has been thrown by the target of an invocation. The code is
When I click the VS 2010 icon to open it I get a popup box error "Exception has been thrown by the target of an invocation". I then need to right click the icon, click "Run as.." change "Current user" to "The Following user" then enter in my windows credentials and it opens fine. This is happening suddenly (Windows XP) and I don't know why. It wasn't happening before and I haven't started logging in with a different user or anything.
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:
I've been tinkering with Delegates, and now Multicast delegates. Every time I invoke two delegates It only displays one of the two delegates per invocation.
I am developing an application with "Visual Studio 2008" (in language VB.NET, Framework: 3.5) with data server as "SQL SERVER EXPRESS 2005".
i have one table with name [fyr] and it contains two columns 'fyid' (integer) and 'fyear' (nvarchar(50)).following queries are showing exception as "No data exists for row/column"
Dim cmd As New OleDbCommand("SELECT * FROM fyr WHERE fyear= '" & DateTime.Now.ToString("yy") & "-" & DateTime.Now.ToString("yy") + 1 & "'", Connection.Instance) Dim cmd As New OleDbCommand("select * from fyr where fyear = '12-13'", Connection.Instance) Dim bdr As OleDbDataReader = cmd.ExecuteReader()
both queries above has same result.but all these queries are working if executed directly in "SQL SERVER Management Studio" and showing the expected results.and connection is in open state all other queries in the project are executing correctly and successfully.The table has the data like this:
I keep getting the error message "Index out of range exception" when I run the following code. XX GN3 = (Loops * 5) For a = 1 To Loops For b = 1 To GN3 R1 = Seeds1(Counter1) Randomize() R2 = CInt(Int((56 * Rnd(R1)) + 1)) Counter1 += 1 MessageBox.Show(R1 & " " & Counter1 & " " & b & " " & GN3) Next b Next a
The message box conforms that the last entry in the array has been reached. And that Counter1 and b both start at 1 and go to 2845. And that GN3 is also 2845 all of the time.
I have a form with binding sources and a method for saving the data.[code]I was testing to see what would happen if the operator tried entering duplicate data in the primary key field. They exception occurred as I expected but the program gets stuck at that point. The exception messagebox just keep redisplaying when you click OK. I'm fairly new to .Net, but this code is how the help files show updating a TableAdapter using the "Try/Catch".
Imports Excel = Microsoft.Office.Interop.Excel Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
I'm looking for some pointers on implementing Custom Events in VB.NET (Visual Studio 2008, .NET 3.5). I know that "regular" (non-custom) Events are actually Delegates, so I was thinking of using Delegates when implementing a Custom Event. On the other hand, Andrew Troelsen's "Pro VB 2008 and the .NET 3.5 Platform" book uses Collection types in all his Custom Events examples, and Microsoft's sample codes match that line of thought. So my question is: what considerations should I have when choosing one design over the other? What are the pros and cons for each design? Which of these resembles the inner-implementation of "regular" events?
Below is a sample code demonstrating the two designs. Public Class SomeClass Private _SomeEventListeners As EventHandler Public Custom Event SomeEvent As EventHandler AddHandler(ByVal value As EventHandler) _SomeEventListeners = [Delegate].Combine(_SomeEventListeners, value) [Code] .....
I am trying to retrieve an image from a table in sql 2005 server. The field is set to image. I am trying to put the image strait into a picture box.
Here is my code I am using: Dim strSQL As String = Nothing strSQL = "select top 1 i.image_data" & _ " from " & mdlMainLib.GetNGConfigInfo(False, False, True) & ".dbo.person as p" & _ " inner join " & mdlMainLib.GetNGConfigInfo(False, False, True) & ".dbo.images as i on p.image_id = i.image_id" & _ " where person_id = '" & sPersonID & "'" [Code] .....
On the line ME.pb1.image = image.fromstream(stream) I keep getting a "ArgumentException was unhandled, Parameter is not valid." And that all I get to go on.
I have most of the obvious user error handled with code, limits to mubers on keypress, if statement in case of input blank left blank etc.. I realize though that are infinintepossibliltys the user can perform especially with the programI am trying to create it requires ALOT of user interaction, with users inputting information (numbers in textboxes) and calculations happen on the fly, in other words there is no Calculate button after everything is input
i am using visual studio 2005 and sql 2005 currently i am doing a system registration for staff using windows form,in the system new staff must register they detail, once user type his detail than this error is come out here i attach the picture and coding. I also highlight where is probleam come out for your info my database name is databse name is = login, table name is staff. using will put their detail in text such i write below after doing that i try to click button registe and suddenly this error come out.[code]
Catch exception handing in .Net easy could it be to add an Ignore, Retry, Cancel when an exception is caught? Or how do we implement something like it?
I have a form with a button that brings up a different form. In some versions of this program (don't ask), the second form is shown non-modally, but in my version it is shown modally. The point of that last statement is that the second form can be either modal or non-modal, so an answer needs to handle either one, but the modal option is more valuable.If form 2 throws an exception that is not handled, the exception is caught somewhere on Form1, though the exact place that it is caught is largely dependent on where the exception was thrown from. The question is this: I need a means to trap all exceptions raised on Form2 or anything called from Form2 such that no exception EVER propagates out of Form2 to be caught in Form1. The reason for this is that Form2 HAS to perform some cleanup for reasons that I have zero control over. That cleanup doesn not absolutely require user input, but it would be good to have some.Is there any event that is fired if a form is exited due to a call stack unwinding as an unhandled exception propagates up the stack?
