ApplicationEvents.vb Not Catching Unhandled Exceptions?
May 5, 2011
While I understand ApplicationEvents.vb won't catch exceptions in another thread, is there any reason why it shouldn't catch exceptions in the UI thread? From time to time I get exceptions that simply crash the program, even though an exception handler is defined as follows:
Private Sub MyApplication_UnhandledException(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.ApplicationServices.UnhandledExceptionEventArgs) Handles Me.UnhandledException
I have a VB.NET application (VS2010, .NET 4.0) that seems to throw an exception under some unknown conditions after a number of hours. In addition to the main thread, there are additional threads running. In reading this link: [URL] it seems like this would be a big help in trapping this exception. I have what are probably some very basic questions:
1. I assume ErrorHandlerForm() in the example refers to the main form of the application, setup.vb in my case. Therefore the last line in the example should be:
[Code]...
I would have expected to to replace ErrorHandlerForm.Form1_UIThreadException with find a setup event such as Setup_UIThreadException but there doesn't appear to be sucn an event.
Take the TripPriceService.wsdl from this link Add a service reference(ServiceReference1) to a windows application, by giving the wsdl from the mentioned wsdl file saved in local folder. My question has two parts
1) Is the below fault message a valid soap fault as per the wsdl(TripPriceServiceException)?
2)Now How to handle and catch the detail tag, when the response is a soap:fault?
Imports windowsapp1.ServiceReference1 Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim obj As New ServiceReference1.TripPriceServiceFacadeClient
[code]....
The line obj.getTripPrice, invokes the service. However will it throw an exception if the response is a soap fault(of type TripPriceServiceException)? How to handle such cases, do we need to use ServiceReference1.TripPriceServiceException? We are in a need to handle such faults in our webservice client.
How do i catch an exception for the following piece of code?
If File.Exists(Path)Then
m_TempTable.ReadXml(Path,XmlReadMode.ReadSchema)
I deliberately deleted some code from the xml file to replicate a corrupt file but cannot catch the exception before the program trips up. I want to be able to notify the user there is a corrupt file and get them to re-install it.I have tried trying and catching but the debugger always stops with an XmlSchemaException at - m_TempTable.ReadXml(Path,XmlReadMode.ReadSchema)
The xml file is static information that needs no changing or saving. Would another way of storing this info be better?
I've a control that throws an exception in one of its events and I need to catch this exception. How can I do this?
Example: Private Sub AxNtlxImage_Reason(ByVal sender As Object, ByVal e As AxNTLXIMAGELib._DNtlxImageEvents_ReasonEvent) Handles AxNtlxImage.Reason ' TODO: Deal with this reason message Throw New ArgumentException(e.sText) End Sub
I want to catch this exception from another procedure when it happens.
I'm writing a SSIS 2005 script (vb.net)in which I want the functionality to checks if a file exists if so then delete it.For testing purposes I'm renaming files to replicate an exception i.e. file cannot be read for whatever circumstance,to ensure the error handling is correct.The code works fine and catches any errors with the File.Exists(errorLookUpLog File) command, if the file does not exist/cannot be read but not with the code below using System.IO.File.Delete(lookupErrorLogFile) as when file is renamed and therefore cannot be deleted (looking for the file under it's original name then no exception is shown (see full code below, have yet to try catching specific exception for if a files doesnt exist)[code]
How does one handle unhandled exceptions in a DLL? VS doesn't give me the option to add Application Events, I'm guessing because it's a DLL. Do I just have to do it in the main app?
Is there anything similar to the MyApplication_UnhandledException for an user control in VB? I would like to have a central point where to catch all unhandled exceptions of a user control, without propagating the exception to the application that uses the user control. I made some test raising an exception in a method of my user control where there is no try/catch code (of course in the true project all methods have a try/catch block). The exception was caught by MyApplication_UnhandledException event of the application using the user control. But this is too "far" from the point where the exception happens and in worst case the user should restart the application.
I would like to realize a behaviour for the user control in order that if the user control fails, the exception is not propagated till the application, but just caught at user control level.
I would like to catch any exceptions from any method in a class so that I may record class specific data to the exception for logging before it is passed up the stack. I know that I can put a try-catch in every method of the class, but there are many methods and It seems there should be a more efficient way. Example of what I am currently doing:
I have some code in my ApplicationEvent.vb to handle The problem is that I need to execute a procedure that has a dataset table adapter in it.Obviously as I want it to run in batch mode I can't have a table adapter as they are GUI based (or at least I think they are) so I am getting this error:
'V_SyncStatusTableAdapter' is not a member of 'AppName.My.MyApplication' For this code: If Me.V_SyncStatusTableAdapter.GetData.Rows.Count > 0 Then
I've just skipped around a few inbuilt VB classes' methods which throws exception. of all that i've came across, methods may throw multiple exceptions but ALL of them are exclusive, meaning there is no way 2 exceptions will ever occur simultaneously, yea and i was trying to make my class throw 2 exceptions simultaneously, hence this question, must all exceptions be exclusive?
I am trying to convert a VB.NET project to C#. I am conveting all the forms and classes as required, but I don't know where I need to write the events from ApplicationEvents.vb (I believe its autoGenerated from Properties) Here is the code in my ApplicationEvent.vb file:
I am trying to catch an exception but occasionally get an inner exception. I want to output both into a label. I often get Object reference not set to instance of an object if there is no inner exception.
Catch ex As Exception exError = ex.Message.ToString If Not ex.InnerException.Message Is Nothing Then
When I debug a program my IDE simply does not catch System.NullReferenceException - execution continues as if there were nothing wrong.Moreover, when I go to the menu Debug/Exceptions System.NullReferenceException is not even in the list(Common Language Runtime Exceptions).
I manually add it (there is the Add button) and I put a checkmark in the 'Thrown' and 'User unhandled' column - now IDE catches it, but after I re-load the project the situation re-appears - and NullReferenceException is not on the list again. What may be wrong?
Update:No, when I step through the code the execution does not continue but exits the current block of code (sub or function). There were no Try...Catch blocks and there is a message: A System.NullReferenceException occured in MSCorlib.dll... But why doesn't the debugger stop at this line?
I have a simple function which tries to get a value from an Obout grid filter column, and if the value is empty, ignores it and moves on. For some reason this code ignore my catch block and always shows a System.FormatException when the input string is empty More bizarre, if I use visual studio's debugger and set a breakpoint on that line, the catch block functions normally (after I continue from that line). I have already confirmed that my Debug | Exceptions | CLR are not set to catch when thrown. I have also confirmed this same behavior in the production version.
I have 5 errors that come up every time I run my project They are all "A first chance exception of type 'System.ArgumentException' occurred in System.Drawing.dll"
I have try catch blocks around every piece of code I have written, and it does not seem to catch them, so I opted to catch the appdomain.UnHandledException.
That does not seem to catch them either If I step through the code line by line (several hundred lines so I hold down f8) it does not make the error...
Only when I run full speed.
I can only figure that I am accessing something maybe before an object is completely drawn, however how in the heck would anyone suggest I go about finding it, and why will my global event handler not catch them?
I am using BackgroundWorker to connect asynchronously to a database. Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]...
While my connection is being opened, I have a "Loading" animation show in a lblCalibration. Once it's connected, the animation stops successfully and shows the calibrated record that I am fetching from my db.
However, if there is an error while connecting to my db for any reason, it does not work. My app freezes. The reason is because I am trying to make a cross-thread call while trying to Catch the error in the DoWork event.[URL]..
but still cannot seem to make any progress. Does anyone have any tips or advice on how to properly catch the error and still run BackgroundWorker?
'SHEETS For Each ctrl As Control In Me.Controls What am I doing wrong here? When I put in manual text after the line return it fill in but as is it doesn't pick up all the checkboxes under HEADINGS. It does create all the sheets under SHEETS.
Code: If (TypeOf ctrl Is CheckBox AndAlso CType(ctrl, CheckBox).Checked) AndAlso CType(ctrl, CheckBox).Name.Contains("Sheet") Then wb.Worksheets("Template").copy(after:=sheet)
I'm not even sure if that's what I want.But, here's my question. I have written a small program to automate the running of some files. These files have the potential to give an error in the form of a MessageBox which will halt the whole process. Is there a way to detect if that window pops up so that I can kill the process so the next file can run.
Also, if I can get the location of this MessageBox, is it possible to get text out of it so that maybe I can email myself the error so that the processes can keep running but I cango to that file and fix it.
I put a try/catch block around a bit of code that occasionaly throws an expected exception, but rather than catching it and displaying the message box, it stops the debugger and alerts me that the exception is unhandled.How do I handle this exception so my code doesn't stop when the exception occurs?
Friend myDevInfo As New devInfo ''' <summary> ''' Closes the device handle obtained with CreateFile and frees resources.
I am not sure what would cause this. I see a lot of people using JavaScript to go around the problem however I do not know how to write JavaScript code.
How can this be done (preferably without JavaScript)?
I made a application in VB.Net. But some users face crash upon startup. That is "A problem caused this program from working correctly" with just one button "Close the program". Since there are lot of things happening when the app loads
I have an ArrayList that is populated with Objects. These Objects raise events at certain times. How can I capture these events from the ArrayList? i.e. I want something like this: Public Sub MyRaisedEvent(ByVal obj as MyObject) Handles MyArrayList.MyEvent End Sub
I have a method as follows: Public Sub Send() Dim caughtException As Exception = Nothing Try //Attempt action. Catch ex As Exception //Custom exceptions which can be thrown all inherit from Exception. //Instantiate error object to be logged. caughtException = ex End Try //Log action and if there is an error log this too. If caughtException IsNot Nothing Then Throw caughtException End Sub
It is essential that I log the error for reports, which after research, rethrowing the exception is the right thing to do. What I am concerned about is preservation of stack information. In order to keep the code DRY I am logging the action in one place - after the exception has been caught. This functionality is ultimately exposed via WCF.
I have a VB.NET winforms solution, and would like to add the standard application exception handlers - Application.ThreadException and AppDomain.CurrentDomain.UnhandledException.I have the following code from MSDN
' Starts the application. ' <SecurityPermission(SecurityAction.Demand, Flags:=SecurityPermissionFlag.ControlAppDomain)> _ Public Shared Sub Main() ' Add the event handler for handling UI thread exceptions to the event. '
[code]....
How can I do it in VB.NET when I have no acces to the Sub Main() method?Is the case when "Enable Application Framework" of my solution properties is enabled (Sub Main is hidden)...
I run a program multiplying decimals with integers. If a user enters a non 0 number etc. the try catch works its charm. i added some lines to clear the text boxes and that works fine but
lblReva.text = ""
does not clear the labels where the answers are displayed, on the contrary it displays the correct value calculated and enters a 0 for the erroneous entry. I would like to clear all the labels and text boxes(except the instruction and assingment labels)so the form is clean once more so the user can try to be "more on" target next time.
