Try...Catch

lowell · July 14th, 2007, 09:24 AM

I am writing code in VB from Visual Studio 2005 Standard Edition. I find it really nice that a Try...Catch exception actually provides the line number in which the exception occurred.

I wanted to know if the line number was also displayed in a compiled, excuse me, a published program. I created a simple program with a form and no controls. The Form_Load procedure has an intentional error.

Here is the code.

Code:

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim x As Long = 64000
        MessageBox.Show(x.ToString)
        Try
            Dim y = CShort(x)
            MessageBox.Show(y.ToString)
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try
    End Sub

When I run the program in the VB environment it works fine and tells me there is an error in Line 7 {Dim y = CShort(x)}.

Unfortunately, after I publish the program and run it, I get an Unhandled exception...
StartIndex cannot be less than zero.
Parameter name: startIndex

I have not been able to find any information on what this (startIndex) is, where it is, or what to do about it. Any help would be appreciated.

Thanks, Lowell

planoie · July 14th, 2007, 12:06 PM

My understanding is:

When you are building an application in Visual Studio and the application is compiled, .pdb files are created along side the application's assemblies. These .pdb files link the execution points in the MSIL assembly to the lines of code in the code files. They form the bridge. If you remove these, the program will still run, but the runtime will no longer be able to link a execution point in the assembly back to the source code. This introduces some uncertainty to the debugging process for sure.

I'm curious why you say "...compiled, excuse me, a published program". What do you see as the difference.

Have you tried googling the error message to see if you can find something on it? It almost seems that it is coming from somewhere else as it doesn't appear to relate to the code sample you posted.

-Peter

lowell · July 22nd, 2007, 09:31 PM

Googling the error message only told me I was not alone in not understanding this error.

Why "...compiled, excuse me, a published program". Because Microsoft decided to change the name. I really don't see a difference.

Thanks, Lowell

planoie · July 23rd, 2007, 06:35 AM

I'm curious as to what has made you believe that Microsoft has changed the name? I have not heard of such change. I have been compiling lots of .NET code for the last several years, but not never "published" (in Microsoft parlance) any of it, however I have several production web sites running the code that I compiled.

My view is that Microsoft uses the term "publish" as a substitute for "deploy". I guess, technically deploying something implies you are sending it somewhere where as publishing would imply that you are making something publicly available.

-Peter