Re: Parsing Binary Files

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From: Jon Skeet [C# MVP] (skeet_at_pobox.com)
Date: 10/12/04 

Date: Tue, 12 Oct 2004 10:02:05 +0100

Hemang Shah <v-hshah@microsoft.com> wrote:
> Thank you Niki & Jon
>
> I took the sample and it worked for me. I was able to get proper matches.
>
> Now I have some questions if you don't mind me asking:
>
> 1) The code right now is Case Sensitive I guess to the string we want to
> search is that correct ?

Yes.

> 2) If I want it to be not case sensitive, do I type the string in every
> posible combination and search with each of those bytes ? or is there a
> better solution

Well, you could supply multiple byte arrays, and check whether the nth
byte is any of the acceptable ones, rather than just a single
acceptable one. You then just supply a lower case version and an upper
case version - you don't need to come up with every combination.

> 3) What I want to do is, after the search is met, I want to read x amount
> of characters after that search and display it. Now the # of characters
> after the search is not fixed, it could be 1 word or it could be a sentence.
> I would know it because it will truncate with another search string.

To what extent is this *really* a binary file? Pretty much everything
you've said has been in terms of text.

> 4) I don't understand the copying of buffer so that we can check across
> boundries, I understand the concept but I cannot follow the code from there.

I haven't actually looked at Niki's code myself.

> Also, how do I handle my fetching the info if it is across boundries.
> 5) Our input buffer is set to 16 bytes. Is there any reason its 16 ? or it
> could be any size.

It could be set to any size. I'd usually use about 32K myself. 

-- 
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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