Question

I have a file that contains many lines, I am using a streamreader to read the file. What I need to do is count how many lines there are in this file, but at certain points the file contains a line of text as such: “—–“. SO what I need to do is count the number of lines in the file excluding the lines that contains “—–“.

I do not want to use the streamreader like this:

StreamReader reader = new StreamReader();
var x = reader.ReadLine()

and check if x contains “—–” and if it does increment a counter, as this is very intensive as the file would be a huge file.

Any help is much appreciated.

Thanks in advance.

Answer 1

I would use:

var count = File.ReadLines("foo.txt")
                .Count(line => !line.Contains("-----"));

Note that File.ReadLines reads in a streaming fashion, so this will only actually read one at a time.

However, that effectively will do what you’ve described yourself not wanting to do… just in a rather prettier way. You say it’s “very intensive” – but this in inherent work. If you’re trying to count the number of lines containing a certain pattern, you’ve clearly got to read each line. I don’t see how you think that’s avoidable.