using System;

using System.Text;

  using System.IO;

 using System.Security.Cryptography;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine(HashPassword("123456"));

    }

        public static string HashPassword(string plainMessage)

        {

            byte[] data = Encoding.UTF8.GetBytes(plainMessage);

            using (HashAlgorithm sha = new SHA256Managed())

            {

                byte[] encryptedBytes = sha.TransformFinalBlock(data, 0, data.Length);

                return Convert.ToBase64String(sha.Hash);

            }

        }

}