public DataSet ValidateLogin(string UserID, String Password)
    {
        DataSet ds = new DataSet();

        helpus.OpenConnection();
        SqlDataAdapter da;

        try
        {
            da = new SqlDataAdapter("sp_ValidUser", helpus.GetConnection);
            da.SelectCommand.CommandType = CommandType.StoredProcedure;
            if (UserID.ToString() == "")
            {
                da.SelectCommand.Parameters.Add("@userid", SqlDbType.VarChar).Value = DBNull.Value;
            }
            else
            {
                da.SelectCommand.Parameters.Add("@userid", SqlDbType.VarChar).Value = UserID.ToString();
            }
            if (Password.ToString() == "")
            {
                da.SelectCommand.Parameters.Add("@password", SqlDbType.VarChar).Value = DBNull.Value;
            }
            else
            {
                da.SelectCommand.Parameters.Add("@password", SqlDbType.VarChar).Value = Password.ToString();
            }

            da.Fill(ds);
            return(ds);
        }
        catch (Exception ex)
        {
            throw ex;
        }
        finally
        {
            helpus.CloseConnection();
        }
    }