Question

If i got a text file

“dont run if you cant hide, or you will be broken in two strings, your a evil man”

and i want to count how many times the word you is in the text file, and put that value in to a int variable.

how do i go about doing somthing like that?

Answer 1

Assuming there are regular line breaks then if the file is huge this would be less memory intensive than some other approaches here. Uses Jason’s counting method:

        var total = 0;
        using(StreamReader sr=new StreamReader("log.log"))
        {

            while (!sr.EndOfStream)
            {
                var counts = sr
                    .ReadLine()
                    .Split(' ')
                    .GroupBy(s => s)
                    .Select(g => new{Word = g.Key,Count = g.Count()});
                var wc = counts.SingleOrDefault(c => c.Word == "you");
                total += (wc == null) ? 0 : wc.Count;
            }
        }

Or, combining the Scoregraphic’s answer here with a IEnumerable method:

    static IEnumerable<string> Lines(string filename)
    {
        using (var sr = new StreamReader(filename))
        {
            while (!sr.EndOfStream)
            {
                yield return sr.ReadLine();
            }
        }
    }

You could get a nifty one-liner

    Lines("log.log")
        .Select(line => Regex.Matches(line, @"(?i)\byou\b").Count)
        .Sum();

[Edited because System.IO.File now supports enumerating the lines of a file, removing need for hand rolled method of doing the same thing described above]

Or using framework method File.ReadLines() you could reduce this to:

File.ReadLines("log.log")
        .Select(line => Regex.Matches(line, @"(?i)\byou\b").Count)
        .Sum();