public List<Disease> GetllDiseases()
        {
            List<Disease> diseases=new List<Disease>();

            SqlConnection connection = new SqlConnection(connectionstring);

            string query = "SELECT * FROM Table_Disease";

            SqlCommand command = new SqlCommand(query, connection);

            connection.Open();

            SqlDataReader reader = command.ExecuteReader();

            while (reader.Read())
            {
               Disease disease=new Disease();

                disease.Id = int.Parse(reader["diesease_Id"].ToString());
               disease.Name = reader["disease_Name"].ToString();
               disease.Description = reader["disease_Description"].ToString();
               disease.TreatmentProcedure = reader["disease_TreatmentProcedure"].ToString();

                diseases.Add(disease);
            }

            return diseases;
        }
        public int Insert(Disease disease)
        {
            SqlConnection connection =new SqlConnection(connectionstring);

            string query = "INSERT INTO Table_Disease VALUES('"+disease.Name+"','"+disease.Description+"','"+disease.TreatmentProcedure+"')";

            SqlCommand command=new SqlCommand(query,connection);

            connection.Open();

            int rowsAffected = command.ExecuteNonQuery();

            connection.Close();

            return rowsAffected;
        }
        public string Insert(Disease disease)
        {
            if (disease.Name == "")
            {
                return "disease name is missing";
            }

            else if (disease.Description == "")
            {
                return "disease description is missing";
            }

            else if (disease.TreatmentProcedure == "")
            {
                return "disease treatment procedure is missing";
            }

            else if (diseaseGateway.HasThisDiesesName(disease.Name))
            {

                return "disease name already exists";
            }

            else
            {
                int value = diseaseGateway.Insert(disease);

                if (value > 0)
                {
                    return "Saved Successfully";
                }

                else
                {
                    return "Operation Failed";
                }
            }
        }