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Counting lines in a string

Great analysis!I found out that Regex can be accelerated by a factor of about two.Instead of new Regex(@"\n", RegexOptions.Compiled|RegexOptions.Multiline);you can speed up by using:new Regex(@"^.*?$", RegexOptions.Compiled|RegexOptions.Multiline);But admittedly, nothing beats...

Alternatives

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9 Jan 2012
Grasshopper.iics
Can't we have something as below?int n=(s.Split(new char[]{'\n'})).Length;where n is the number of lines?
10 Jan 2012
Luc Pattyn
You shouldn't be working with huge strings at all.If this represents a file's content, read it using File.ReadAllLines() and take the array's Length.Otherwise, count the lines while you collect the data, not afterwards.Dealing with a huge string isn't doing the caches any favors.And if...
17 Jan 2012
Jon Bellamy
Again, going with other people's comments about memory, how about using a Streamreader? (I haven't tested the timings (or code) but from memory..This should be fast (and memory efficient)...at least in my experience.StreamReader sr = new StreamReader("Put file here");Int32 cnt =...
9 Jan 2012
akemper
I've compared your favorite with seven alternatives:static long LinesCount(string s) { long count = 0; int position = 0; while ((position = s.IndexOf('\n', position)) != -1) { count++; position++; // Skip this occurance! } ...
18 Jun 2012
OriginalGriff
8 alternatives  
It seems like an obvious requirement, but the .NET framework will not count occurrences of a character in a string. It's easy to do, but which way is the quickest?
11 Jan 2012
George Swan
How about using the extension method: return s.Count(c => (c == '\n'));
17 Jan 2012
Greg Baryza
I had to do something like this in XSLT. If the string is not too long (for some definition of "too long"), you can replace all newlines with "" and then take the difference in the two string lengths.
17 Jan 2012
Roman Shero
Hello! Great tip!What do you think about this extension method:public static class StringExtension{ public unsafe static long LineCount(this string s) { long lineCount = 1; fixed (char* pchar = s) { char* p = pchar; for (; *p...

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Andreas Gieriet
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