c# - Is this a bad practice to catch a non-specific exception such as System.Exception? Why?

Question

I am currently doing a code review and the following code made me jump. I see multiple issues with this code. Do you agree with me? If so, how do I explain to my colleague that this is wrong (stubborn type...)?

• Catch a generic exception (Exception ex)
• The use of "if (ex is something)" instead of having another catch block
• We eat SoapException, HttpException and WebException. But if the Web Service failed, there not much to do.

Code:

try
{
    // Call to a WebService
}
catch (Exception ex)
{
    if (ex is SoapException || ex is HttpException || ex is WebException)
    {
        // Log Error and eat it.
    }
    else
    {
        throw;
    }
}

Answer 1

The mantra is:

• You should only catch exceptions if you can properly handle them

Thus:

• You should not catch general exceptions.

---

In your case, yes, you should just catch those exceptions and do something helpful (probably not just eat them--you could throw after you log them).

Your coder is using throw (not throw ex) which is good.

This is how you can catch multiple, specific exceptions:

try
{
    // Call to a WebService
}
catch (SoapException ex)
{
    // Log Error and eat it
}
catch (HttpException ex)
{
    // Log Error and eat it
}
catch (WebException ex)
{
    // Log Error and eat it
}

This is pretty much equivalent to what your code does. Your dev probably did it that way to avoid duplicating the "log error and eat it" blocks.