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CSharp · Console

/Program.cs

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();
	}
}