public static string SHA1Encrypt(string sourceText)

       {

           SHA1 sha = new SHA1CryptoServiceProvider();

           ASCIIEncoding enc = new ASCIIEncoding();

           byte[] dataToHash = enc.GetBytes(sourceText);

           byte[] dataHashed = sha.ComputeHash(dataToHash);

           string hash = BitConverter.ToString(dataHashed).Replace("-", "");

           return hash;

       }