RE: Check value is number only

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Brendan Grant <grantb@xxxxxxxxxxxxxxx> wrote:
> Code readability is always good, however there are times when performance is
> more important than readability, and with extensive testing one can
> dramatically reduce the risk of such a complicated regular expression from
> causing you issues.
>
> While using a Parse() may be simpler and more readable, I disagree that it
> is more efficient.

I don't think you read my post properly. I wasn't suggesting *just*
using int.Parse - I was suggesting a simple method to test for just
digits (without using a regular expression) followed by a call to
Parse.

> Usage of either depends on which side you want to pay the
> penalty of an unparseable value.
>
> If it is a parseable value being passed in, then yes, Parse() faster, an
> order of magnitude faster in the best case. On the other hand, if a lot of
> invalid values are being dealt with, using the Regex method can be in the
> best case ~50 times faster than Parse().

Whereas a hard-coded test followed by int.Parse can be about 50x faster
than Regex.

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

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