How to Encrypt and Decrypt string?

Solution:
Following code examples show the way. It requires two references to include:

using System.Text;

using System.Security.Cryptography;

public static string Encrypt(string toEncrypt, bool useHashing)

        {

            byte[] keyArray;

            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

            string key = "MySeCrEtKeY";

            if (useHashing)

            {

                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();

                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));

                hashmd5.Clear();

            }

            else

                keyArray = UTF8Encoding.UTF8.GetBytes(key);

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();

            tdes.Key = keyArray;

            tdes.Mode = CipherMode.ECB;

            tdes.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = tdes.CreateEncryptor();

            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            tdes.Clear();

            return Convert.ToBase64String(resultArray, 0, resultArray.Length);

        }

public static string Decrypt(string cipherString, bool useHashing)

        {

            byte[] keyArray;

            byte[] toEncryptArray = Convert.FromBase64String(cipherString);

            string key = " MySeCrEtKeY";

            if (useHashing)

            {

                MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();

                keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));

                hashmd5.Clear();

            }

            else

                keyArray = UTF8Encoding.UTF8.GetBytes(key);

            TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();

            tdes.Key = keyArray;

            tdes.Mode = CipherMode.ECB;

            tdes.Padding = PaddingMode.PKCS7;

            ICryptoTransform cTransform = tdes.CreateDecryptor();

            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

            tdes.Clear();

            return UTF8Encoding.UTF8.GetString(resultArray);

        }

Hope this will help.