Encryption and Decryption in c# windows form application

namespace : using System.Security.Cryptography

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

namespace encryptAndDecrypt
{
    public class Encryptor
    {       
        private static readonly byte[] _key = { 0xF1, 0x46, 0xA6, 0xBB, 0xA2, 0x5A, 0x37, 0x6F, 0x81, 0x2E, 0x17, 0x41, 0x72, 0x2C, 0x43, 0x27 };      

        private static readonly byte[] _initVector = { 0xE1, 0xF1, 0xA6, 0xBB, 0xA9, 0x5B, 0x31, 0x2F, 0x81, 0x2E, 0x17, 0x4C, 0xA2, 0x81, 0x53, 0x61 };

        protected internal static string Encrypt(string value)
        {
            if (string.IsNullOrEmpty(value))
                return string.Empty;

            byte[] Value = Encoding.UTF8.GetBytes(value);
            SymmetricAlgorithm mCSP = new RijndaelManaged();
            mCSP.Key = _key;
            mCSP.IV = _initVector;
            using (ICryptoTransform ct = mCSP.CreateEncryptor(mCSP.Key, mCSP.IV))
            {
                using (MemoryStream ms = new MemoryStream())
                {
                    using (CryptoStream cs = new CryptoStream(ms, ct, CryptoStreamMode.Write))
                    {
                        cs.Write(Value, 0, Value.Length);
                        cs.FlushFinalBlock();
                        cs.Close();
                        return Convert.ToBase64String(ms.ToArray());
                    }
                }
            }
        }

        protected internal static string Decrypt(string Value)
        {
            SymmetricAlgorithm mCSP;
            ICryptoTransform ct = null;
            MemoryStream ms = null;
            CryptoStream cs = null;
            byte[] byt;
            byte[] _result; mCSP = new RijndaelManaged();
            try
            {
                mCSP.Key = _key;
                mCSP.IV = _initVector;
                ct = mCSP.CreateDecryptor(mCSP.Key, mCSP.IV);
                byt = Convert.FromBase64String(Value);
                ms = new MemoryStream();
                cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
                cs.Write(byt, 0, byt.Length); cs.FlushFinalBlock();
                cs.Close();
                _result = ms.ToArray();
            }
            catch (Exception ex)
            {
                _result = null;
                throw ex;
            }
            finally
            {
                if (ct != null)
                    ct.Dispose();

                if (ms != null)
                    ms.Dispose();

                if (cs != null)
                    cs.Dispose();
            }
            return ASCIIEncoding.UTF8.GetString(_result);
        }
    }
}
       

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace encryptAndDecrypt
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnEncrypt_Click(object sender, EventArgs e)
        {
            if (rchInputEncrypt.Text != "")
                rchOutPut.Text = Encryptor.Encrypt(rchInputEncrypt.Text);
        }

        private void btnDecrypt_Click(object sender, EventArgs e)
        {
            if (rchInputDecrypt.Text != "")
                rchOutPut.Text = Encryptor.Decrypt(rchInputDecrypt.Text);
        }       
    }
}