ProgramDataHandler.cs

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace GymManagementApp
{
    internal class ProgramDataHandler
    {
        private string conn = "Data Source=ShakeelsXPS\\SQLEXPRESS01;Initial Catalog=GymDB;Integrated Security=SSPI";

        public DataTable GetAllPrograms()
        {
            using (SqlConnection con = new SqlConnection(conn))
            {
                SqlDataAdapter adapter = new SqlDataAdapter("SELECT * FROM Programs", con);
                DataTable dt = new DataTable();
                adapter.Fill(dt);
                return dt;
            }
        }

        public void AddProgram(int id, string name, string desc, string instructor, string schedule, int capacity, string duration)
        {
            string query = $"INSERT INTO Programs VALUES ('{id}', '{name}', '{desc}', '{instructor}', '{schedule}', '{capacity}', '{duration}')";
            ExecuteNonQuery(query, "Program added successfully.");
        }

        public void UpdateProgram(int id, string name, string desc, string instructor, string schedule, int capacity, string duration)
        {
            string query = $"UPDATE Programs SET Name='{name}', Description='{desc}', Instructor='{instructor}', Schedule='{schedule}', Capacity='{capacity}', Duration='{duration}' WHERE ProgramID='{id}'";
            ExecuteNonQuery(query, "Program updated successfully.");
        }

        public void DeleteProgram(int id)
        {
            string query = $"DELETE FROM Programs WHERE ProgramID='{id}'";
            ExecuteNonQuery(query, "Program deleted successfully.");
        }

        private void ExecuteNonQuery(string query, string successMessage)
        {
            using (SqlConnection con = new SqlConnection(conn))
            {
                SqlCommand cmd = new SqlCommand(query, con);
                try
                {
                    con.Open();
                    cmd.ExecuteNonQuery();
                    MessageBox.Show(successMessage);
                }
                catch (Exception ex)
                {
                    MessageBox.Show("Error: " + ex.Message);
                }
            }
        }
    }
}