DatabaseHelper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Online_Food_Order_System
{
    using System;
    using System.Collections.Generic;
    using System.Data;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    using MySql.Data.MySqlClient;

    namespace Online_Food_Order_System
    {
        internal class DatabaseHelper
        {
            public static string connectionString = "Server=localhost;Database=online_food_order_system;Uid=root;Password=TE891DUZ;";
            public static void ExecuteNonQuery(string query, params MySqlParameter[] parameters)
            {
                using (MySqlConnection conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    using (MySqlCommand cmd = new MySqlCommand(query, conn))
                    {
                        if (parameters != null)
                            cmd.Parameters.AddRange(parameters);

                        cmd.ExecuteNonQuery();
                    }
                }
            }

            // For SELECT queries (returns DataTable)
            public static DataTable ExecuteQuery(string query, params MySqlParameter[] parameters)
            {
                using (MySqlConnection conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    using (MySqlCommand cmd = new MySqlCommand(query, conn))
                    {
                        if (parameters != null)
                            cmd.Parameters.AddRange(parameters);

                        using (MySqlDataAdapter adapter = new MySqlDataAdapter(cmd))
                        {
                            DataTable dt = new DataTable();
                            adapter.Fill(dt);
                            return dt;
                        }
                    }
                }
            }

        }
    }

}