[Mono-list] Npgsql error

[Emil Emilov]

Ok, but how does an exception fit in? You need to know if there was an error to log it or do additional stuff (like MsgBox.Show etc.).

Jaroslaw Kowalski wrote:
>> Cool, a question on that:
>> What happens if a exception occurs?
>> I meand close() gets called at the end of the using block, but does it 
>> get also called when an exception occurs (sort of finally)?
>> If yes, I'm changing my programming style :)
>> Another question, how would it look like if you had to catch an 
>> exception (i.e. to rollback a transaction)?
> 
> 
> The following code:
> 
> ====
> using (A a = new A())
> {
>    code
> };
> ====
> 
> Is equivalent to:
> 
> =======
> A a = null;
> 
> try
> {
>    a = new A();
>    /// code
> }
> finally
> {
>    if (a != null) ((IDisposable)a).Dispose();
> }
> =======
> 
> It's the C# compiler that translates every using() to something like the 
> above code. The IDisposable.Dispose method on data providers 
> automatically rolls back any open and uncommitted transactions so you 
> don't need to do explicit rollbacks.
> 
> BTW. I've seen many (MS and other) examples where they don't call 
> Dispose the IDbCommand object, even though it implements IDisposable, 
> I'm not sure whether it leads to potential resource leaks or not.
> 

-- 
Emil R. Emilov
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