1) How is ON ERROR GOTO -1 used? I don't understand the help text.
2) ON ERROR seems to be deprecated. What is the recommended Try...Catch replacement for ON ERROR RESUME NEXT. ie. where I have a series of commands, any of which may throw an exception, and I want to ignore all exceptions yet attempt every command?
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'm new to visual basic and i'm trying to expand my programming knowledge by creating random projects that include personal advantages. Right now I am trying to create a program that prescribes a series of commands necessary for the execution of game emulators with the touch of a couple buttons. ive created a gui of sorts ... i just don't know to make it function.
[Code]...
I ran into an interesting dilemna today. I have a function that handles information and checks for duplicate values, then returns the next number that is not a duplicate. So, I have something like this:
Public Function GetNextNonDuplicateNumber(NumberToCheck as Long) as Long
//the non-duplicate the function will return
Dim NonDuplicate as Long
'duplicate
If CheckForDuplicate(NumberToCheck) = True Then
Throw New DuplicateException()
[Code] .....
As you can see, I want to handle the exception specifically, but I also want to throw it when I'm done because I want to alert other code outside the function. The problem is that simply throwing it exits out of the function with a null value.
I have written a VB.NET 2.0 code and in my code i am calling class.Showdialog and for that i am getting thread exception. I have mentioned the call stack of the exception. Can any one help me out to resolve this issue. [code]
View 5 RepliesAssume you have the following code:
Instead of doing:
Try
'
[code].....
while my first .net steps I want to understand and test the Method
Private Sub MyApplication_UnhandeledException in ApplicationEvents.vb.
But if I throw an exception the IDE stops and says "unhandled exception" and gives solution tips.
Is it possible to switch off those exception warnings and run through the unhandeled exception handling in ApplicationEvents.vb ?
I'm not getting any errors, or anything I just forgot how to do error checking in the "set" portion of properties
I have 3 Classes, my frmMain,Sales and a Validator Class
Code for the Validator Class:
CODE:
Code for my Sales Class:
CODE:
I need to Throw an Excepton when the Sales price is Zero or negitive and when the trade in allowance is negtive I'm not quite sure how to do that in the Object Oriented Manner.
If I have an existing exception object (I'm not in a catch block, I just happen to have been given an exception object), is there any way (re)throw it while preserving it's stack trace?
The context for asking is that I'm writing a RunWorkerCompleted handler. If an error happened while running the background task, then this will have shown up in the Error property of the RunWorkerCompletedEventArgs. To keep the code simple I want to use the same error handling code to trap this, or any error that happens later during the handler. That means I need code like this:
Private Sub OnDone(ByVal sender As Object, ByVal e As RunWorkerCompletedEventArgs)
[Code]...
I don't think that using an InnerException here (ie. saying something like Throw new Exception(ex)) will work because then I have the problem that my Catch block has no way of knowing whether the exception it's supposed to be handling is the outer one or an inner one. StackOverflow seems to have various similar questions, but I've not found anything that describes this particular situation.
When I print to the printer, using the PrintDocument, I want it to be able to throw an exception if there is a problem. Currently, if I print to a printer that has a jam, is offline, or doesn't even exist, VB still thinks it printed fine. I never get an error. How can I have the printer report back to my program so that if I print to a printer that doesn't even exist, it wont let me do it? I just tried adding a LPT1 printer to my computer (and there is no local printer). I called it some random printer and installed some random driver. Then used my program to print to that printer and never got an error.
View 1 RepliesI want to throw error, if i used methods from this namespace System.IO
For example,
If i write File.Delete("TempPath") , i have to throw undefined Method..
Having problems with null dates in a mysql table. Have eventually found out that I can store a 'null' date in mysql as "0000-00-00" and I can run the 'insert' command to add a record to the mysql table. When I check on mysql workbench I can see the row has been inserted correctly and the date shows as "0000-00-00".However...When I try to load the table into a datagridview, I get an error = mysql Conversion Exception was unhandled = "Unable to convert MySQL date/time value to System.DateTime".
View 4 RepliesI have below program that throw exception. Do you know how to fix??
Dim conn As New SqlCeConnection
conn.ConnectionString = "Data Source=" & Dir & StockTakeFile & ";Persist Security Info=False"
conn.Open()
Dim cmd As New SqlCeCommand("select * from TableStockTake", conn)
Dim reader As SqlCeDataReader
reader = cmd.ExecuteReader()
[Code]...
If I throw an exception from within a catch, does the finally (from the catch) still execute? i.e.
Try
..some code with an exception in it...
catch ex as Exception
throw new SpecialException("blah blah" & ex.Message, ex)
[code]....
I'm writing some code in which I need to use my own HttpResponse object to capture the output from a method on another object that takes an HttpResponse as a parameter. The problem is, this other object (which I cannot modify) calls HttpResponse.End(), which causes an "Object reference not set to an instance of an object" exception to be thrown. What can I do about this?
Dim myStringbuilder As New StringBuilder
Dim myStringWriter As New IO.StringWriter(myStringbuilder)
Dim myResponse As New Web.HttpResponse(myStringWriter)
[code].....
i have vb 2005 and i dont know how to make Ctrl+S work so that it throws a messagebox on the screen.ive tried a couple of different threads, looking for my answer and i cant seem to find it. its just a simple application, but i want to spice it up a bit with a shortcut to save the info on the screen.i dont want to deal with the saving part yet, but just to get vb to recognize that the user pressed the Ctrl key and the s key in combination.
View 5 RepliesI am catching sql exception from databse as shown below.[code]Now I want to throw exception by adding some userfiendly information,Like below.Throw SQLexception + "my message.....".
View 8 RepliesIs there a way to throw multiple exceptions?
i tried to throw an exception in the Finally block but somehow the exception in the Finally block overrides the first exception that i wanted to throw
[color=#CC66CC]hiiiiiiiiiiiiii every one[/color]
[color=#FF6666]
how can I connect to oracle 10g XE database throw the Internet using Visual Studio .Net? I mean how can I get what I want from my DB using the Internet and what is the compatible version of Visual Studio .Net with oracle 10g XE?[/color] [color=#330033]I wanted to work with oracle Jdevloper but I could not understand anything realy and could not find somthing to show how to start it even :blink:?
This one has me completely confused. I'm using the function below in a .vb file (it's the only function in the file as of right now).
[Code]...
Is it possible to loop throw all usercontrols in a winform.
I wanna run this treatment within a for each and it loop all usercontrols
Usercontrol11 is one of 20 usercontrols existing in a form (usercontrol11,usercontrol12, etc )[code]...
I wanted a Message Box to appear when a file can't be found, for example. I made a Combo Box (ComboBox1) and a button, this is what the code was:[code]If a file can't be found, I want a message box to appear, not an Error Provider, I tried this code, but it did not work:[code]
View 2 RepliesI think I have a problem with the provider smtp.Is this the problem? why cant I send SMS? [code]
View 21 RepliesI'm trying to convert a batch of .pngs to .jpgs, as in this question:
[Code]....
The call to jpg.Save, however, with a "generic error" in GDI+. Originally outside of the innermost Using statement, I moved the call inwards as per this answer, but it didn't change anything. I have verified that newfile contains a valid path, and that the program has write access to the directory. What am I missing?
From previous experience I had been under the impression that it's perfectly legal (though perhaps not advisable) to call extension methods on a null instance. So in C#, this code compiles and runs:
// code in static class
static bool IsNull(this object obj) {
return obj == null;
}
[code]....
The debugger stops right there, as if I'd called an instance method. Am I doing something wrong (e.g., is there some subtle difference in the way I defined the extension method between C# and VB.NET)? Is it actually not legal to call an extension method on a null instance in VB.NET, though it's legal in C#?
I'm working with visual studio 2008 developing software for windows CE 6.0, compact framework.I'm having this "strange?" trouble with isNumeric method. Is there another better way to do this job? Why is getting me an exception? (two in facts...both of type FormatException)
dim tmpStr as object = "Hello"
if isNumeric(tmpStr) then // EXCEPTIONs on this line
// It's a number
else
// it's a string
end if
Why does System.Xml.XmlDocument.LoadXml method throw System.Net.WebException ?if MSDN was right, LoadXml should at most give me a System.Xml.XmlException.Yet I have weird exceptions like:The underlying connection was closed: The connection was closed unexpectedly.
Dim document As New XmlDocument
document.LoadXml("<!DOCTYPE html PUBLIC ""-//W3C//DTD XHTML 1.0 Transitional//EN"" ""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd""><x></x>")
MsgBox(document.LastChild.Name)
url...If you check out the images on that website you will notice that in their program, it has the textbox and user icon thing and everything and they have transparencies set.Is there anyway to access those "objects" and just throw it on the screen? How exactly are they doing that? Did they make their own graphics? And if they did, how are they letting it do the transparency, because I know laying a picturebox over a picturebox won't accomplish that.
View 10 RepliesI am updating a legacy application, and it was reading a dll from another project for a Dictionary(of Guid, String) of items and using them.
The requirements have changed, and the method that was returning the Dictionary is now returning an IList.
This is the odd behavior of this; the intellisense is not throwing a cast error, nor is the compiler. It does not throw an error until runtime when it tries to set the Dictionary to the IList.
Example:
Dim someDictionary As Dictionary(Of Integer, String) = New Dictionary(Of Integer, String)
Dim someList As IList(Of Integer)
someDictionary = someList
why the compiler is not catching this?
from the vb web:
Quote:
The following Microsoft intermediate (MSIL) instructions throw OutOfMemoryException :
*
box
*
newarr
*
newobj
Does anyone knows what exactly does box means? and also is there anyway this statement will cause an outofmemory: Dim a As Boolean
What about if its just an empty object: Dim a As someobj