How should I encrypt data to send in URL

I need to encrypt a string which I am sending in a URL and later I need to decrypt it ...

Which approach would be better for this? I tried the following:

string s = "String to be encrypted";

string encrypted = CipherUtility.Encrypt<RijndaelManaged>(s, "pass", "salt");

string decrypted = CipherUtility.Decrypt<RijndaelManaged>(encrypted, "pass", "salt");

But the encrypted string gets an "=" at the end ... I would like to avoid that.

And I am not sure that this would be the best option ...

The CipherUtility is the following:

public class CipherUtility
{
  public static string Encrypt<T>(string value, string password, string salt)
    where T : SymmetricAlgorithm, new()
  {
    DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));

    SymmetricAlgorithm algorithm = new T();

    byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
    byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);

    ICryptoTransform transform = algorithm.CreateEncryptor(rgbKey, rgbIV);

    using (MemoryStream buffer = new MemoryStream())
    {
       using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Write))
       {
          using (StreamWriter writer = new StreamWriter(stream, Encoding.Unicode))
          {
             writer.Write(value);
          }
       }

       return Convert.ToBase64String(buffer.ToArray());
    }
 }

 public static string Decrypt<T>(string text, string password, string salt)
  where T : SymmetricAlgorithm, new()
 {
   DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));

   SymmetricAlgorithm algorithm = new T();

   byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
   byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);

   ICryptoTransform transform = algorithm.CreateDecryptor(rgbKey, rgbIV);

   using (MemoryStream buffer = new MemoryStream(Convert.FromBase64String(text)))
   {
     using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Read))
     {
        using (StreamReader reader = new StreamReader(stream, Encoding.Unicode))
        {
           return reader.ReadToEnd();
        }
      }
    }
  }
}

Thank You, Miguel