Re: VB vs C#

From: Jon Skeet [C# MVP] (skeet_at_pobox.com)
Date: 04/13/04 

Date: Tue, 13 Apr 2004 12:33:21 +0100

Cor Ligthert <notfirstname@planet.nl> wrote:
> > A C# developer can use the Microsoft.VisualBasic namespace if they
> > really want to. I don't remember seeing any examples where it's faster
> > than can be achieved by not using it, however.
>
> We did some test now already again a some long time ago in the language.vb
> group (I did although with comments and test from the others as Jay B.).
>
> The Find from a string is twice as fast as the indexOf method with a string.

I'd be interested to see that thread/benchmark. Do you remember what it
was called?

It's certainly possible that String.IndexOf hasn't been well-optimised,
but I suspect the optimisation could be done just as well in a C#
method if necessary.

> I was also supprissed because I have no real VB classic background, so I
> never use that (still not), as I often told you I think that the 1 as start
> of an index is the best however, I am used to the zero to start an index.

Not sure how that's relevant here...

> The indexOff however outclassed the Find when it is with a real defined char
> at least 10 times in performance (the char Find does not exist).
>
> Not so long ago I did also test with the Replace and was expecting the same
> result. However that MB find had the same speed as the Regex. The
> string.replace was amazing enough the fastest with the stringbuilder.replace
> (that is the one I like) on a very good second place (only a slight
> difference). The test are done by more persons on more places in the world
> on different computers and the methode is checked also by those persons.

Why is it amazing that String.Replace is fast?

> The MB replace and the Regex was 10 to 100 times slower dependable on the
> situation 1000 times a short string or 10 times a long string than the
> string.replace. (It was a very simple Regex).
>
> I hope this gives you some idea's

I'm not at all surprised that Regex was fairly slow. People always seem
to be recommending that one should use a regex when it's just as simple
(and more readable) to use a few string operations.

Regular expressions are incredibly powerful, but most of the time that
power isn't needed. 

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

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