Throw an exception in try catch block

c# exception try-catch-finally
Quincy picture Quincy · Jul 20, 2010 · Viewed 58.9k times · Source 
try { 
  if (isFileDownloaded)
   // do stuff
  else
   throw new CustomException()
} 
catch (Exception e)
{
  // something went wrong to save the error to log
}
finally
{
  //release resources
}

My question is would the catch catches the ApplicationException thrown in the try block? is it in poor coding style?

Should it be written in another way?

Answer

Reed Copsey picture Reed Copsey · Jul 20, 2010

The catch will catch your exception (and any other that occurs). That being said, I try to avoid writing code like this when possible.

Personally, I see little reason to ever have exception handling (catch) for an exception thrown in the same scope. If you can handle your error in your method - put the exception handling (ie: logging) directly in the try block as well.

Using a catch is more useful, IMO, for catching exceptions thrown by methods within your try block. This would be more useful, for example, if your // do stuff section happened to call a method that raised an exception.

Also, I recommend not catching every exception (Exception e), but rather the specific types of exceptions you can handle correctly. The one exception to this would be if you're rethrowing the exception within your catch - ie: using it for logging purposes but still letting it bubble up the call stack.

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