public int?ComproveUserPasswordBD(String Email, String Contraseña) { int? rownumber; SqlConexion conexion = null; SqlCommand command = null; if (Email == null || Email == "") { throw new Exception("Email no valido"); } if (Contraseña == null || Contraseña == "") { throw new Exception("Contraseña no valida"); } try { conexion = new SqlConexion(ListConexion.GetDataSource()); conexion.Open(); command = conexion.CreateCommand(); command.CommandType = System.Data.CommandType.Text; command.CommandText = "Select Count(*) From Usuario Where Email=@Email AND Contraseña=@Contraseña"; command.Parameters.Add(new SqlParameter("@Email", Email)); command.Parameters.Add(new SqlParameter("@Contraseña", Contraseña)); rownumber = command.ExecuteScalar() as int?; } catch (SqlException) { throw new Exception("Error en la consulta"); } catch (Exception) { throw new Exception("Error en la consulta"); } finally { command.Dispose(); conexion.Close(); } return(rownumber); }