Calculater permutations of a string

Permutations.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace dotNetPlayGround
{
    class Permutations
    {
        private static int[] permutationValue = new int[0];
        private static int numberOfElements = default(int);
        private int elementLevel = -1;

        public static void Main()
        {
            Console.WriteLine(MakeCharArray("abc"));
        }

        public static char[] MakeCharArray(string InputString)
        {
            char[] charString = InputString.ToCharArray();
            Array.Resize(ref permutationValue, charString.Length);
            numberOfElements = charString.Length;
            return charString;
        }

        public void CalcPermutation(int r)
        {
            elementLevel++;
            permutationValue.SetValue(elementLevel, r);

            if (elementLevel == numberOfElements)
            {
                //OutputPermutation(permutationValue);
            }
            else
            {
                for (int i = 0; i < numberOfElements; i++)
                {
                    if (permutationValue[i] == 0)
                    {
                        CalcPermutation(i);
                    }
                }
            }
            elementLevel--;
            permutationValue.SetValue(0, r);
        }
    }
}