Connection.cs

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace Hotel_Management_System
{
    internal class DatabaseConnection :IDatabase
    {
        private SqlConnection conn = new SqlConnection("Data Source=DESKTOP-BHPJ89K\\SQLExpress;Initial Catalog=hotel;Integrated Security=True;TrustServerCertificate=True");
        public void openConnection()
        {
            if(this.conn.State == System.Data.ConnectionState.Closed)
            {
                this.conn.Open();
            }
        }
        public bool getConnectionState()
        {
            switch (this.conn.State)
            {
                case System.Data.ConnectionState.Open:
                    return true;
                default:
                    return false;
            }
        }
        public void closeConnection()
        {
            using (SqlConnection conn = this.getConnection())
            {
                if(this.conn.State == System.Data.ConnectionState.Open)
                {
                    this.conn.Close();
                }
            }
        }
        public SqlConnection getConnection()
        {
            return this.conn;
        }
        public SqlCommand executeCommand(string command)
        {
            using (SqlConnection connection = this.conn)
            {
                if(connection.State == System.Data.ConnectionState.Closed)
                {
                    this.openConnection();
                }
                using(SqlCommand cmd =  new SqlCommand(command, conn))
                {
                    return cmd;
                }
            }
        }
    }
}