Mono C#

Implementation of programming language C#

Mono C# is C# compiler developed with Mono project. It is free and open-source. It includes mcs (compiler to target 1.1 runtime), gmcs (to 2.0), smcs (to 2.1) and dmcs (to 4.0).

Links:

Examples:

Hello, World!:

Example for versions Microsoft Visual C# 2008, gmcs 2.0.1 
using System;

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Hello, World!");
    }
}

Factorial:

Example for versions Microsoft Visual C# 2008, gmcs 2.0.1

This example uses recursive factorial definition. 

using System;

class Program
{
    static long Factorial(int n)
    {
        if (n == 0)
            return 1;
        else
            return n * Factorial(n - 1);
    }
    static void Main(string[] args)
    {
        for (int i = 0; i < 17; i++)
            Console.WriteLine("{0}! = {1}",i,Factorial(i));
    }
}

Fibonacci numbers:

Example for versions Microsoft Visual C# 2008, gmcs 2.0.1

This example uses recursive definition of Fibonacci numbers. 

using System;

class Program
{
    static long Fibonacci(int n)
    {
        if (n < 3)
            return 1;
        else
            return Fibonacci(n - 1) + Fibonacci(n - 2);
    }
    static void Main(string[] args)
    {
        for (int i = 1; i < 17; i++)
            Console.Write("{0}, ", Fibonacci(i));
        Console.WriteLine("...");
    }
}

Quadratic equation:

Example for versions Microsoft Visual C# 2008, gmcs 2.0.1 
using System;

class Program
{
    static void Main(string[] args)
    {
        int A, B, C, D;
        try
        {   Console.Write("A = ");
            A = Convert.ToInt32(Console.ReadLine());
            Console.Write("B = ");
            B = Convert.ToInt32(Console.ReadLine());
            Console.Write("C = ");
            C = Convert.ToInt32(Console.ReadLine());
        }
        catch
        {   Console.WriteLine("Invalid input");
            return;
        }
        if (A == 0)
        {   Console.WriteLine("Not a quadratic equation.");
            return;
        }
        D = B * B - 4 * A * C;
        if (D == 0)
            Console.WriteLine("x = {0}", -B / 2.0 / A);
        else if (D > 0)
            Console.WriteLine("x1 = {0}\nx2 = {1}", (-B + Math.Sqrt(D)) / 2 / A, (-B - Math.Sqrt(D)) / 2 / A);
        else
            Console.WriteLine("x1 = ({0},{1})\nx2 = ({0},-{1})", -B/2.0/A, Math.Sqrt(-D)/2/A);
    }
}

CamelCase:

Example for versions gmcs 2.0.1

First line of Main method reads the input string from console and converts it to lowercase. Second line replaces all sequences of 1 or more non-alpha characters with spaces. Two next lines get object of class TextInfo and use it to convert the string to title case (all words start with capital letters). Finally, spaces are removed from the resulting string, and the result is written to console. 

using System;
using System.Globalization;
using System.Text.RegularExpressions;
 
public class Program
{   public static void Main(string[] args)
    {   string text = Console.ReadLine().ToLower();
        text = Regex.Replace(text,"([^a-z]+)"," ");
        TextInfo ti = new CultureInfo("en-US",false).TextInfo;
        text = ti.ToTitleCase(text);
        text = text.Replace(" ","");
        Console.WriteLine(text);
    }
}

CamelCase:

Example for versions gmcs 2.0.1

This example uses only regular expressions. First pass replaces all maximum sequences of letters with result of applying CapitalizePart to them (i.e., makes first character uppercase). Second pass replaces all non-letters with empty string. 

using System;
using System.Text.RegularExpressions;
 
class Program 
{   static string CapitalizePart(Match m) 
    {   string x = m.ToString();
        return char.ToUpper(x[0]) + x.Substring(1, x.Length-1);
    }
    static void Main() 
    {   string text = Console.ReadLine().ToLower();
        string cc = Regex.Replace(text, "([a-z]+)", new MatchEvaluator(Program.CapitalizePart));
        cc = Regex.Replace(cc, "[^a-zA-Z]+", string.Empty);
        Console.WriteLine(cc);
   }
}