Hi all!

I'm trying, and failing, to count the number of non-blank lines in a string in C#. In addition to 'empty lines', I also want to count lines with only 'white space' (spaces, tabs) as blank and I'm not sure how to do that.

The regex that I'm currently using doesn't do this:

var re = new Regex(@"\r?\n", RegexOptions.Multiline);

var count = re.Matches(inString).Count;

Any thoughts on how I might achieve this requirement would be greatly appreciated.

Regards,

mroshaw 

I'm not clear if you want to match non-blank lines or blank lines (even those that contain only whitespace characters) - you r posting seems to be a little contradictory on this. However the pattern you posted would seem to point towards counting blank lines. On the other hand the title is clear about counting non -blank lines.

What your current pattern will do is to simply match the line-feed characters at the end of a line - it says nothing about what else is (or isn't) on that line.

If you are wanting to count non-blank lines, then these can be defined as a line that contains at least one non-whitespace character.Therefore you could use something like

^.*\S.*\r?$

with the "multiline" option set as you have in your pattern.

Alternatively, to count blank lines (allowing for spaces or tabs) then something like

^[ \t]*\r?$

should do. (By the way the character set contains a space and the tab character - if you want other whitespace characters such as the vertical tab, then add those into the the set definition).

Susan