Abstract exception super type
- by marcof
If throwing System.Exception is considered so bad, why wasn't Exception made abstract in the first place?
That way, it would not be possible to call:
throw new Exception("Error occurred.");
This would enforce using derived exceptions to provide more details about the error that occurred.
For example, when I want to provide a custom exception hierarchy for a library, I usually declare an abstract base class for my exceptions:
public abstract class CustomExceptionBase : Exception
{
/* some stuff here */
}
And then some derived exception with a more specific purpose:
public class DerivedCustomException : CustomExceptionBase
{
/* some more specific stuff here */
}
Then when calling any library method, one could have this generic try/catch block to directly catch any error coming from the library:
try
{
/* library calls here */
}
catch (CustomExceptionBase ex)
{
/* exception handling */
}
Is this a good practice?
Would it be good if Exception was made abstract?
EDIT : My point here is that even if an exception class is abstract, you can still catch it in a catch-all block. Making it abstract is only a way to forbid programmers to throw a "super-wide" exception. Usually, when you voluntarily throw an exception, you should know what type it is and why it happened. Thus enforcing to throw a more specific exception type.
