using System;

using System.Security.Cryptography;

using System.Text;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World!");

        Console.WriteLine(ComputeSaltedHash("2uTmG7vMny222VCt","DF#$%345455poursoltanwer@#$et"));   

        Console.WriteLine(HashPassword("","2uTmG7vMny222VCt"));

    }

    private static string Base64Encode(string plainText) {

            var plainTextBytes = System.Text.Encoding.ASCII.GetBytes(plainText);

            return System.Convert.ToBase64String(plainTextBytes);

        }

        public static string Base64Decode(string base64EncodedData) {

            var base64EncodedBytes = System.Convert.FromBase64String(base64EncodedData);

            return System.Text.Encoding.ASCII.GetString(base64EncodedBytes);

        }       

​

        private static string ComputeSaltedHash(string password, string salt)

        {

            // Create Byte array of password string

            var encoder = new ASCIIEncoding();

            var secretBytes = encoder.GetBytes(password);

​

            // Create a new salt

            var saltBytes = encoder.GetBytes(password);                  

​

            var sha1 = SHA1.Create();

            var passHashSh1 = sha1.ComputeHash(secretBytes);

            var saltHashSh1 = sha1.ComputeHash(saltBytes);

            Console.WriteLine(encoder.GetString(passHashSh1));

            Console.WriteLine(encoder.GetString(saltHashSh1));

            var concated = encoder.GetString(passHashSh1) + encoder.GetString(saltHashSh1);

            var concatedBytes = encoder.GetBytes(concated);

            var sha256 = SHA256.Create();

            var hash = sha256.ComputeHash(concatedBytes);

​

            return Base64Encode(encoder.GetString(hash));

        }

    public static string HashPassword(string user, string password)

        {

            var str1 = CalculateSha1String(password);

            var str2 = CalculateSha1String("DF#$%345455poursoltanwer@#$et");

            var a1 = str1 + str2;

            var a2 = CalculateSha256String(a1);

            var a3 = System.Convert.ToBase64String(System.Text.Encoding.ASCII.GetBytes(a2));

            return a3;

        }

​

        public static bool VerifyHashedPassword(string user, string hashedPassword, string providedPassword)

        {

            var providedPasswordHash = HashPassword(user, providedPassword);

            if(hashedPassword.Equals(providedPasswordHash))

                return true;

            return false;

        }

        private static string CalculateSha1String(string text)

        {

            var sha1 = new SHA1CryptoServiceProvider();

            var hash = sha1.ComputeHash(Encoding.ASCII.GetBytes(text));

            string strHex = "";

            foreach (byte b in hash) strHex += $"{b:x2}";

            return strHex;

        }

​

        private static string CalculateSha256String(string text)

        {

            var sha256 = new SHA256CryptoServiceProvider();

            var hash = sha256.ComputeHash(Encoding.ASCII.GetBytes(text));

            string strHex = "";

            foreach (byte b in hash)

            {

                strHex += String.Format("{0:x2}", b);

            }

​

            return strHex;

        }

}