Should I use Try Catch Block to implement my Business Logic?

Question

Suppose I need something like this.( This code is blunder, but just an example). This code is not my problem! Its just an example. I know how to write it using if else statements. I'm considering a more complicated Context!

int[] arraynums = new int[3] {1,2,3};
int Sample = 0;
try
{
Sample = arraynums[3];
}
catch
{
Sample=4;
}

Here I can use an alternative logic which wont't run into an error. But still I can reduce the code if I use try catch block. Is it advisable to use a try catch block to solve a logic? If no, then why?

if you're going to do do that at least do `catch(IndexOutOfRangeException)` As it stands you're catching everything. — Conrad Frix, Mar 18 '13 at 05:11
Ah so *that's* how people end up with the ingenious try/catch loop design. — Voo, Mar 18 '13 at 07:34

score 6 · Accepted Answer · edited May 23 '17 at 12:01

For following reason you should not use exception to implement business logic (or flow control):

This is not a good practice. It would confuse the other devs, even you would be confused after 6 month.(This violates the PrincipleOfLeastAstonishment. This makes it harder for programmers to read.)
Exception is costly.
Bad design.

There are fairly good amount of material available in other posts:

There is whole wiki about it: http://c2.com/cgi/wiki?DontUseExceptionsForFlowControl

score 3 · Answer 2 · answered Mar 18 '13 at 04:49

3

Why not using an if-statement?

if(arraynums.length > 3)
{
    Sample = arraynums[3];
}
else
{
    Sample = 4;
}

answered Mar 18 '13 at 04:49

Eng.Fouad

107,075
62
298
390

I know it. but can I use it like that? – Subin Jacob Mar 18 '13 at 04:51
2

Of course you can use it like that! Why not try it yourself before asking questions like this? – griegs Mar 18 '13 at 04:52
Can I use try catch like that?. I knew it could be used like that using if statements. But if I felt that try catch is simpler in a different context, can I use it there to solve the problem? – Subin Jacob Mar 18 '13 at 05:02
3

@SubinJacob - I think you're confusing **can** and **should**. **can** is on topic for this site, which has been answered, but **should** is off-topic because it'll likely solicit debate. Try http://programmers.stackexchange.com for a discussion on design patterns. – beatgammit Mar 18 '13 at 05:16

p.s.w.g · Answer 3 · 2013-03-18T04:58:57.130

3

I'm assuming your code is fairly contrived, since it's pretty easy to rewrite it without an exception. Exceptions are relatively expensive for the run-time. They can needlessly slow down your code if abused. In general, you should check for exceptional conditions before you allow them to be thrown.

Should I use Try Catch Block to implement my Business Logic?

4 Answers4