What types of exceptions should be thrown for invalid or unexpected parameters in .NET? When would I choose one instead of another?
Follow-up:
Which exception would you use if you have a function expecting an integer corresponding to a month and you passed in '42'? Would this fall into the "out of range" category even though it's not a collection?
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 have a form where it is validating three fields. I want to have it so if an exception has been thrown in any of the three fields that the code that is in the button does not run and it redoes the validation.
View 4 RepliesI'm using Vista Ultimate x64 to develop on and I have found that any unhandled exceptions that I would expect to get thrown in the Load event of a form do not actually get thrown... This happens no matter which compile mode I select (x86, x64 or AnyCPU). If I copy the exact same EXE to an XP machine then the unhandled exception is thrown as expected and the JIT debugger warning message appears. Its very annoying as absolutely no indication that an exception has occurred is shown, the program just loads normally but anything after where the exception should have been thrown is not executed. For example, if I create a new project now and stick this in the form load event then the program would just load as if nothing has gone wrong:
My.Computer.FileSystem.ReadAllText("----")
OS: Win7 64bits Software Tools:Package and Deployment Wizard (for VB6.0)The vbp file is working in XP. Installed the VB6.0 in Win7 64bits, it can make the exe file.However, the setup file can be made using the 'Package and Deployment Wizard' Tool.
View 2 RepliesI have a relatively simple VB.NET app. It targets framework 2.0 from Visual Studio 2010. The app works fine most of the time, except that the users sometimes receive the
following exceptions. The error is completely random and somewhat rare. I haven't been able to trap it while in a development environment. It also doesn't appear to be
pointing at my code. My app continues to run if the users ignore the error. How would I trap and handle this error?
Several of my overriden Equals methods have started throwing Invalid Cast Exceptions -
Unable to cast object of type 'System.DBNull' to type Common.ResolveUser'.
This occurs when binding List (of T) (where T is of type ResolveUser in this case) to a combo.
Equals Method:
Public Overrides Function Equals(ByVal obj As Object) As Boolean
Dim i As ResolveUser = CType(obj, ResolveUser)
If i.UniqueResolveID = UniqueResolveID Then Return True
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This may be a debugger issue, but here goes:I have this piece of code:
Private Function Connect() As Boolean
Try
sessionBegun = False[code].....
My intention is to 'convert' the low level exception into something more meaningful, so I throw an exception of my own creation. I want this to bubble up to a place where I can handle it.However what is happening is my debugger breaks and tells me that an exception of type "QuickBooksConnectionException" was thrown.I know that, I just threw it, why are you catching it? From what I've read, this ought to work, and there doesn't appear to be an analogous Java throws keyword, so perhaps it is my debugger.
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?
View 1 RepliesMy console errors out when I enter anything other than a number or operators in the designated (input). I stink at this stuff but I have been t this for about 8 hrs. still not there. I have included a text file for the task at hand
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I'm using WMI code and VB 2008 to see NIC status. So far the queries are working, but the methods aren't. For example, I'm trying to set a network card to use DHCP, I get invalid function with this code:
Dim classInstance As New ManagementObject("rootCIMV2", "Win32_NetworkAdapterConfiguration.Index='7'", Nothing)
Dim outParams As ManagementBaseObject = classInstance.InvokeMethod("EnableDHCP", Nothing, Nothing)
I'm getting Invalid column name 'CHARLES'. Invalid column name 'CHARLYN'. Invalid column name 'SMITH'.what's wrong with my code, it's been a long time since I used SQL dataset. I'm into LINQ but I'm having problems with this kind of LINQ query so I'm reverting to SQL dataset.here's my code:
'Set up a data set command object.
Dim sSelectColumn As String = ("SELECT * FROM tblScanned WHERE LastName=" & sLastName & " AND FirstName =" & sFirstName & " AND MiddleName =" & sMiddleName)[code].....
I'm writing a query to select all records that has any part of parameter. I have one table called Employees. Some people have name like this: John David Clark If the parameter is
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I should be able to get result back as long as there's a match in the parameters. If I use Function Contains (q.FirstName & " " & q.LastName).Contains(employeeName), I will not get any result back if employeeName is "John Clark" Function Contains looks only for next words from left to right. It doesn't match a single word at a time. So that's why I used this in the Linq to SQL:
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where I was encrypting the string and passing it to another web page to decrypt and get the ids to be displayed as a pdf back to the page. I kept getting an invalid "Invalid length for a Base-64 char array". It was then I realised that the string was getting truncated and that the IE Explorer had a size limit for the number of charaters being passes as a querystring.So I think I need to go the route of posting it.But not sure how to go about it.
Private Sub GetReport()
Try
Dim hawbs As String = String.Empty[code]....
The retrieve document then does: the decrpytion gets the data(ids) and pulls the pdfs.
I am getting error [07002] the # binded parameters < the # of parameters makers, i checked both parameters were perfect even though i am getting this error here is my code
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How can we prevent/stop unexpected Exception in .net. In my applicaiton there is an exception occurs randomly (sometimes my application works fine very long time, but sometimes that exception occurs and my application close). I do the following thing for prevent that unexpected exception.
In my Visual Studio 2008 -> Debug Menu -> Exceptions - > and unchecked all (Throw) and In User-unhandled all items are checked. But still i got that error.
In duplicated code using Lockbits in VB to obtain the address of Bitmap.Scan0, the first is OK, in all applications, but the second NEVER is. What is the explanation please? Surely both StartAddrA and StartAddrB should be valid pointers to Bitmap.Scan0 for calls to valid, functional ASM code in the functional DLL. The error is, it seems, in the VB Lockbits process. Using VS2010 Beta 2 and XP.
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Basically Commands has Parameters and parameters has functions like Add, AddWithValue, and etc. In all tutorials i've seen, i usually noticed that they are using Add instead of AddWithValue.
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since it saves my coding time. So which is better to use? Which is safe to use? Does it improves performance?
is there a way to get the GET parameters and POST parameters in just one function or Collection in ASP.NET? Like using $_REQUEST in PHP? I'm using VB.NET.
View 3 RepliesI'm flummoxed I'm using VB.Net, Linq, and a DataContext. My DataContext contains a table 'transactions'.
I first declare an IQueryable(Of transaction) and assign it to nothing. I build a predicate in a foreach loop and use a transactions.Where(predicate) to assign the IQueryable a value. If I do an IQueryable.ToList(), I get a number of items in the collection.
However, on the next iteration of the loop, the IQueryable.ToList() gives me 0 items.This is driving me crazy. I tried to use the LINQ to SQL Debug Visualizer with VS2010, (I recompiled the 2008 version with the new reference) but no dice - I can't see the SQl generated or what's inside the IQueryable.
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How do I fix this error? I'm using asp.net Compilation Error.Description: Error compiling a resource required to service this request. Review your source file and modify it to fix this error.
Compiler Error Message: CS1519: Unexpected symbol `Dim' in class, struct, or interface member declaration
Source code:<%@ Import Namespace="System.Data.OleDb" %>
<script runat="server">
sub Page_Load
Dim dbconn As OleDbConnection
dbconn=New OleDbConnection("Provider=SQLOLEDB;
Data source='http://localhost';
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I've inherited a VB website (I'm a C# developer by trade) and need to do some changes. On loading it into VS2010 it won't compile/run because it has a <!-- --> pair surrounding some code in the style section of each form and VS is saying this is an unexpected character sequence.I'm assuming it's a vb comment tag, but I've Googled it to with either making VS accept them, or advice on what to change them to so the original intent is not lost. NB I've tried <%-- which I use in C# but that doesn't appear to work either.
Example:
<html>
<head>
[code].....
Just when I was thinking that I had Linq To Xml sussed I'm faced with yet another error! I think if I was to understand the linq search process in general better I might have more success, so any good links regarding that are also welcome. To my problem however; using the code below:
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I am using following to get path to 'My Documents' folder in Windows 7 and iterate through its directories:
Dim diri As New DirectoryInfo(Environment.GetFolderPath(Environment.SpecialFolder.Personal))
For Each diri In diri.GetDirectories
MessageBox.Show(diri.Name)
Next
One of the message boxes I get is for a 'My Music' folder. I do not have that folder in the 'My Documents' folder.
In this line of code ".lim" is underlined and the error is that an End Of statement is expected,i wrote End Of at the end of teh code and the error did not dissappear.
Dim FileName As String = lsp ".lim" 'string containing the file name.
If you're not living on the edge, you're taking up too much room
I am writing an app in VB2005 that makes a call to my cars ECU. It sends ok but during the DataReceived event I am getting an unusual result.I am trying to find out how many bytes are in the buffer so I can set up an array to write the data to so I have used the following.
intBTR = _Port.BytesToRead
_Port.Read(bytIncoming, 0, intBTR -1)
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Ok so i have a date time picker that holds a date that was entered by a user. My program works fine when ran on a computer using English(US) regional settings, but when i take it to a computer running any other regional settings, I.E. English(UK), which is the 2nd most common regional settings that will find its way to this program, I recieve an error because the Date format is backwards. What i'm curious about is how can i grab the system Regional Date format in order to rearrange my Date to fix its context?
I know that since the date is stored as a string i'm going to do something along the lines of this to break it apart:
Dim temp()
temp = Split(inputarray(7), "/")
inputarray(7) = temp(1) & "/" & temp(0) & "/" & temp(2)
i am almost 100% sure the above code will take a date in MM/DD/YYYY format and rearrange it to DD/MM/YYYY format.
Receiving following error:Error occured: An unexpected error occurred with the method.
Stack Trace: at MSProject.TimeScaleValue.get_Value()
We have an application (Vb6) that gets installed at all of our client sites and they often (Vista/Windows 7) run into a the error message Unexpected error, quiting after a install on a new machine. The problem comes about when the UAC is on and the application is trying to create registry entries in areas it doesnt have access to because the application is running as a standard user. If the user runs the application as an admin the first time, everything sets up and life if good.
My question is, what is the most elegant way to setup those registry keys without forcing the user to run as an admin the first time? We could force them to run the applicaiton as an admin using a manifest file, but I dont want them to have to run as an
admin every time, just the first time.
I'm having problems with the following Linq query (demandNb is a filter option, as a string):
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My goal is to get all demands for the database if the filter fields is empty. If there is a filter, the function should return all demands that match the filter. Currently, when I try to convert the IQueryable collection to a list using .ToList(), the following error is thrown: Conversion from string "" to type 'Double' is not valid.
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