using System;

using System.IO;using System.Text;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(WrapText.Wrap("Hello World", 10));

    }

​

}

​

public static class WrapText

{

    public static string Wrap(this string text, int width)

    {

        var result = new StringBuilder();

​

        using (var sr = new StringReader(text))

        {

            string line;

            while ((line = sr.ReadLine()) != null)

            {

                if (result.Length > 0) result.AppendLine();

                result.Append(WrapLine(line, width));

            }

        }

​

        return result.ToString();

    }

​

    public static string WrapLine(this string text, int width)

    {

        var result = new StringBuilder();

        var line = new StringBuilder();

​

        var words = text.Split(' ');

​

        foreach (var word in words)

        {

            if (line.Length + word.Length >= width)

            {

                if (result.Length > 0) result.AppendLine();

                result.Append(line.ToString());

                line.Clear();

            }

​

            if (line.Length > 0) line.Append(" ");

            line.Append(word);

        }

​

        if (line.Length > 0)

        {

            if (result.Length > 0) result.AppendLine();

            result.Append(line.ToString());

        }

​

        return result.ToString();

    }

}