using System;

using System.Text.RegularExpressions;

​

public class Simple

{

    static string StripLinefeeds(Match m)

    {

        string x = m.ToString(); // Get the matched string.

        return x.Replace("\n", "");

    }

​

    public static void Main()

    {

        Regex re = new Regex(@""".+?""", RegexOptions.Singleline);

        MatchEvaluator me = new MatchEvaluator(StripLinefeeds);     

        string text = "\n\"this is some text \n this should not be on the new line\"";

        Console.WriteLine(text);

        text = re.Replace(text, me);

        Console.WriteLine(text);

        text = "\n\"this is some \n text \n\n\n this should not be \n\n on the new line\"";

        Console.WriteLine(text);

        text = re.Replace(text, me);

        Console.WriteLine(text);

    }

}