Throwing exceptions created with reflection

[kaloianm]

Hi,

Does someone know whether it is a bad practice to create exception
objects through reflection and throw them? I want to use this in order
to dynamically convert from an integer errorCode to an exception (via a
map errorCode -> typeof( Exception))?

Assembly excAssembly = _exceptionType.Assembly;
Object [] args = new Object [ 1] { _errorCode };
Exception e =
(Exception)excAssembly.CreateInstance( _exceptionType.FullName,

false,

BindingFlags.CreateInstance,

null,

args,

null,

null);
throw (e);

Thanks in advance,
Kaloian.

[Nicholas Paldino [.NET/C# MVP]]

Kaloian,

Well, what are your concerns? I mean, when you throw the exception, you
just throw it. Granted, the idea of mapping an integer code to an exception
is a little odd to me, since I think that the integer code is enough (and
you don't necessarily have to throw an exception).

I think there is a difference between an error code and an exception,
but in the end, it's up to you.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

<ka******@gmail.com> wrote in message
news:11**********************@g47g2000cwa.googlegr oups.com...

Hi,

Does someone know whether it is a bad practice to create exception
objects through reflection and throw them? I want to use this in order
to dynamically convert from an integer errorCode to an exception (via a
map errorCode -> typeof( Exception))?

Assembly excAssembly = _exceptionType.Assembly;
Object [] args = new Object [ 1] { _errorCode };
Exception e =
(Exception)excAssembly.CreateInstance( _exceptionType.FullName,

false,

BindingFlags.CreateInstance,

null,

args,

null,

null);
throw (e);

Thanks in advance,
Kaloian.

[John]

That's very bad code practice.
Exceptions are too expensive to use for processing, don't do that.

If your entire objective is to raise an Exception, then how can it be bad
practice?

What are you up to?
"ka******@gmail.com" wrote:

Hi,

Does someone know whether it is a bad practice to create exception
objects through reflection and throw them? I want to use this in order
to dynamically convert from an integer errorCode to an exception (via a
map errorCode -> typeof( Exception))?

Assembly excAssembly = _exceptionType.Assembly;
Object [] args = new Object [ 1] { _errorCode };
Exception e =
(Exception)excAssembly.CreateInstance( _exceptionType.FullName,

false,

BindingFlags.CreateInstance,

null,

args,

null,

null);
throw (e);

Thanks in advance,
Kaloian.

[Jon Skeet [C# MVP]]

John <Jo**@discussions.microsoft.com> wrote:

That's very bad code practice.
Exceptions are too expensive to use for processing, don't do that.

What exactly do you mean by "for processing"? Whether exceptions are
too expensive depends on how often the relevant situation will occur,
and what the performance demands are.

Just how expensive do you believe exceptions are?

Without trying it (or following the link yet) how many exceptions do
you think can be thrown in a second? You may well be surprised.

See http://www.pobox.com/~skeet/csharp/exceptions.html for my take on
the issue.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too