Counting lines in a file

[jabailo]

Which would be faster for counting lines in a StreamReader:

(a) iterate through a file using .ReadLine() and adding to a counter, i++

(b) doing a .ReadToEnd() and then using an IndexOf() method to count the
occurances of \r\n

(c) doing a .ReadToEnd() and using a RegEx to count the number of occurances
of \r\n


--
Texeme Textcasting Technology
http://www.texeme.com

[wbekker]

Hi Javailo,

I would guess that option c scales better, but a small test might show
the real winner ;-)

Ward

ja*****@texeme. com wrote:

Which would be faster for counting lines in a StreamReader:

(a) iterate through a file using .ReadLine() and adding to a counter, i++

(b) doing a .ReadToEnd() and then using an IndexOf() method to count the
occurances of \r\n

(c) doing a .ReadToEnd() and using a RegEx to count the number of occurances
of \r\n

[Bob Powell [MVP]]

I haven't tested but probably A for any arbitrary length of file.

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<ja*****@texeme .com> wrote in message
news:Nf******** ************@sp eakeasy.net...

Which would be faster for counting lines in a StreamReader:

(a) iterate through a file using .ReadLine() and adding to a counter, i++

(b) doing a .ReadToEnd() and then using an IndexOf() method to count the
occurances of \r\n

(c) doing a .ReadToEnd() and using a RegEx to count the number of
occurances
of \r\n


--
Texeme Textcasting Technology
http://www.texeme.com

[Dmytro Lapshyn [MVP]]

Hi,

I think (b) should be the fastest, but I wouldn't expect any significant
difference between (a) and (b) since Windows does efficient disk read
buffering behind the scenes.
I think (c) should be the slowest because of RegExp.

Anyway, it's all just guessing, why don't you try all the three approaches
and post the real result here? ;-)

--
Sincerely,
Dmytro Lapshyn [Visual Developer - Visual C# MVP]
<ja*****@texeme .com> wrote in message
news:Nf******** ************@sp eakeasy.net...

Which would be faster for counting lines in a StreamReader:

(a) iterate through a file using .ReadLine() and adding to a counter, i++

(b) doing a .ReadToEnd() and then using an IndexOf() method to count the
occurances of \r\n

(c) doing a .ReadToEnd() and using a RegEx to count the number of
occurances
of \r\n


--
Texeme Textcasting Technology
http://www.texeme.com

[Cor Ligthert]

Hi,

Giving my guess as well A/B ex aquo as first.

:-)

Cor

[Chad Z. Hower aka Kudzu]

"ja*****@texeme .com" <ja*****@texeme .com> wrote in
news:Nf******** ************@sp eakeasy.net:

Which would be faster for counting lines in a StreamReader:
The only way to find out is to test it, and in fact different ones may be faster depending on size and
characteristics of the file.
(a) iterate through a file using .ReadLine() and adding to a counter,
i++
This is probably the best over all considering memory considerations etc if your file is large. And
probably the fastest too.
(b) doing a .ReadToEnd() and then using an IndexOf() method to count
the occurances of \r\n

(c) doing a .ReadToEnd() and using a RegEx to count the number of
occurances of \r\n

Both of these will consume large amoutns of memory if the file is large.
--
Chad Z. Hower (a.k.a. Kudzu) - http://www.hower.org/Kudzu/
"Programmin g is an art form that fights back"

Develop ASP.NET applications easier and in less time:
http://www.atozed.com/IntraWeb/

[Ignacio Machin \( .NET/ C# MVP \)]

hi,

the first option is the way to go, unless you are 100% sure that the size of
the file in advance.

The others solutions are not portable, you should use
Environment.New Line() instead of "\r\n"

cheers,

--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation

<ja*****@texeme .com> wrote in message
news:Nf******** ************@sp eakeasy.net...

Which would be faster for counting lines in a StreamReader:

(a) iterate through a file using .ReadLine() and adding to a counter, i++

(b) doing a .ReadToEnd() and then using an IndexOf() method to count the
occurances of \r\n

(c) doing a .ReadToEnd() and using a RegEx to count the number of
occurances
of \r\n


--
Texeme Textcasting Technology
http://www.texeme.com