Warning Message (Exception ex)

dbcook8 · December 1st, 2008, 04:58 PM

I am receiving the following warning message when I do a build:

C:\BegASPNET\Site\Controls\ContactForm.ascx.cs(77, 26): warning CS0168: The variable 'ex' is declared but never used

Here is the code:

try
        {
            mySmtpClient.Send(myMessage);
        }
        catch (Exception ex)
        {
            lblMessage.Text = "An error occurred while sending your e-mail. Please try again.";
        }

Why might I be getting this error?

Imar · December 1st, 2008, 05:18 PM

Hi there,

The warning is telling you that you declare a variable (ex) that you never use.

The ex variable is declared in the catch block but then you never use it. Either get rid of it altogether, or use it for something useful. That is, change the code to this:

Code:

catch (Exception)
{
  lblMessage.Text = "An error occurred while sending your e-mail. Please try again.";
}

or this

Code:

catch (Exception ex)
{
  lblMessage.Text = "An error occurred while sending your e-mail. Please try again. Details: " + ex.Message;
}

The latter is not a good solution as it provides detailed error information to the client. However, it's good to now you can access the ex variable so you can log it to an error log like a database for example.

For more info and detailed explanations:

http://www.google.com/search?hl=en&q...+never+used%22

Cheers,

Imar

---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of Beginning ASP.NET 3.5 : in C# and VB, ASP.NET 2.0 Instant Results and Dreamweaver MX 2004
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