C#/.NET string magic to remove comment lines from text file input?

Question

Say you have a text file you read in as a long string:

123 123 123
123 123 123
// Just a comment
123 123 123    
123 123 123
# Just a comment
123 123 123

You typically split it in to lines something like this, (example in Unity3D),

    List<string> lines = new List<string>(
        controlFile.text.Split(new string[] { "\r","\n" }, 
        StringSplitOptions.RemoveEmptyEntries));

.NET offers an incredible amount of string magic, such as formatting and more.

I wonder, is there some available magic to easily remove comments?

NOTE - of course one can do this using a regex, etc. As SonerGönül points out it can usefully be done with .Where and .StartsWith

My question, is there some facility in the universe of .NET string magic, which specifically "understands" and helps with comments.

Even if the answer from an expert is "definitely no" that's a useful answer.

Answer 1

You can try like this:

var t= Path.GetTempFileName();
var l= File.ReadLines(fileName).Where(l => !l.StartsWith("//") || !l.StartsWith("#"));
File.WriteAllLines(t, l);
File.Delete(fileName);
File.Move(t, fileName);

So you can basically copy the contents of your original file into a temp file which does not have comments line. Then delete the file and move the temp file to original file.

Answer 2

Hope that this will make sense:

 string[] comments = { "//", "'", "#" };
 var CommentFreeText = File.ReadLines("fileName Here")
                       .Where(X => !comments.Any(Y => X.StartsWith(Y)));

You can populate the comments[] with the comment symbols that you want to remove from the textFile. While reading the text it will eliminate all the lines that start with any of the comment symbols.

And you can write it back using:

File.WriteAllLines("path", CommentFreeText);