C#

user_password = cipher_utility.Encrypt<RijndaelManaged>(result, "xxxx", "xxxxxxxxx");

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security.Cryptography;
using System.IO;

namespace Application_Class_Library
{
    public class cipher_utility
    {
        public static string Encrypt<T>(string value, string password, string salt) where T : SymmetricAlgorithm, new()
        {
            DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));

            SymmetricAlgorithm algorithm = new T();

            byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
            byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);

            ICryptoTransform transform = algorithm.CreateEncryptor(rgbKey, rgbIV);

            using (MemoryStream buffer = new MemoryStream())
            {
                using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Write))
                {
                    using (StreamWriter writer = new StreamWriter(stream, Encoding.Unicode))
                    {
                        writer.Write(value);
                    }
                }

                return Convert.ToBase64String(buffer.ToArray());
            }
        }

        public static string Decrypt<T>(string text, string password, string salt) where T : SymmetricAlgorithm, new()
        {
            DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));

            SymmetricAlgorithm algorithm = new T();

            byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
            byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);

            ICryptoTransform transform = algorithm.CreateDecryptor(rgbKey, rgbIV);

            using (MemoryStream buffer = new MemoryStream(Convert.FromBase64String(text)))
            {
                using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Read))
                {
                    using (StreamReader reader = new StreamReader(stream, Encoding.Unicode))
                    {
                        return reader.ReadToEnd();
                    }
                }
            }
        }
    }
}

comboBoxLSKFontSize.Items.Add("10";);
comboBoxLSKFontSize.Items.Add("11";);
comboBoxLSKFontSize.Items.Add("12";);
comboBoxLSKFontSize.Items.Add("13";);
comboBoxLSKFontSize.Items.Add("14";);
comboBoxLSKFontSize.Items.Add("15";);
comboBoxLSKFontSize.Items.Add("16";);
stringLSKFontSize = "14";
i = 0;
foreach (string str in comboBoxLSKFontSize.Items)
{
    if (stringLSKFontSize == str)
    {
        comboBoxLSKFontSize.SelectedIndex = i;
        break;
    }
    i++;
}

byte[] arr = new byte[6] { 68, 65, 84, 65, 13, 10 };
string str = Encoding.ASCII.GetString(arr);

[DllImport("TestERP.dll", CallingConvention = CallingConvention.StdCall)]
    private static extern int GetArray(string baseval,ref int nb,ref IntPtr array,IntPtr msg);

    [DllImport("TestERP.dll", CallingConvention = CallingConvention.StdCall)]
    private static extern int freeMemory( int nb, ref IntPtr array);


public static void GetManagedArray()
    {
         string[] tmp = new string[12];
         int nb = 0;
         IntPtr msg = Marshal.AllocHGlobal(256);
         string tmp2 = "";
         IntPtr intArr = IntPtr.Zero; 

         //call the C function which return the arry of string intArr
         GetArray("val",ref nb,  ref intArr,msg);

         //copy in managed string array
         for (int i = 0; i < nb; i++)
            tmp[i] = Marshal.PtrToStringAnsi(Marshal.ReadIntPtr(intArr, i * IntPtr.Size));

         tmp2 = Marshal.PtrToStringAnsi(msg);

         Marshal.FreeHGlobal(msg);

         //call the C function whiec free memory
         freeMemory(nb, ref intArr);

         intArr = IntPtr.Zero;

         GC.Collect();

    }

int __stdcall GetArray(char base[],int* nb,char*** array,char* outmsg)
{
    int i =0;

    (*array) = (char**)calloc(12, sizeof(char*));

    for (i = 0; i < 12; i++)
    {
        (*array)[i] = calloc(256,sizeof(char));
        sprintf((*array)[i],"%s %d",base,i) ;
    }

    *nb= 12;

    strcpy(outmsg,"message erreur");

   return 0;
}

int __stdcall freeMemory(int nb,char*** array)
{
    int i =0;

    for (i = 0; i < nb; i++)
    {
        free((*array)[i]);
        (*array)[i] = NULL;
    }

    free((*array));

    *array = NULL;

    return 0;
}