Lesson 19.5 - Changing dropdown default values

Player.cs

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

namespace Engine
{
    public class Player : LivingCreature
    {
        public int Gold { get; set; }
        public int ExperiencePoints { get; set; }
        public int Level 
        {
            get { return ((ExperiencePoints / 100) + 1); }
        }
        public Location CurrentLocation { get; set; }

        public Weapon CurrentWeapon { get; set; }

        public List<InventoryItem> Inventory { get; set; }
        public List<PlayerQuest> Quests { get; set; }

        private Player(int currentHitPoints, int maximumHitPoints, int gold, int experiencePoints) : base(currentHitPoints, maximumHitPoints)
        {
            Gold = gold;
            ExperiencePoints = experiencePoints;

            Inventory = new List<InventoryItem>();
            Quests = new List<PlayerQuest>();
        }

        public static Player CreateDefaultPlayer()
        {
            Player player = new Player(10, 10, 20, 0);
            player.Inventory.Add(new InventoryItem(World.ItemByID(World.ITEM_ID_RUSTY_SWORD), 1));
            player.CurrentLocation = World.LocationByID(World.LOCATION_ID_HOME);

            return player;
        }

        public static Player CreatePlayerFromXmlString(string xmlPlayerData)
        {
            try
            {
                XmlDocument playerData = new XmlDocument();

                playerData.LoadXml(xmlPlayerData);

                int currentHitPoints = Convert.ToInt32(playerData.SelectSingleNode("/Player/Stats/CurrentHitPoints").InnerText);
                int maximumHitPoints = Convert.ToInt32(playerData.SelectSingleNode("/Player/Stats/MaximumHitPoints").InnerText);
                int gold = Convert.ToInt32(playerData.SelectSingleNode("/Player/Stats/Gold").InnerText);
                int experiencePoints = Convert.ToInt32(playerData.SelectSingleNode("/Player/Stats/ExperiencePoints").InnerText);

                Player player = new Player(currentHitPoints, maximumHitPoints, gold, experiencePoints);

                int currentLocationID = Convert.ToInt32(playerData.SelectSingleNode("/Player/Stats/CurrentLocation").InnerText);
                player.CurrentLocation = World.LocationByID(currentLocationID);

                if(playerData.SelectSingleNode("/Player/Stats/CurrentWeapon") != null)
                {
                    int currentWeaponID = Convert.ToInt32(playerData.SelectSingleNode("/Player/Stats/CurrentWeapon").InnerText);
                    player.CurrentWeapon = (Weapon)World.ItemByID(currentWeaponID);
                }

                foreach(XmlNode node in playerData.SelectNodes("/Player/InventoryItems/InventoryItem"))
                {
                    int id = Convert.ToInt32(node.Attributes["ID"].Value);
                    int quantity = Convert.ToInt32(node.Attributes["Quantity"].Value);

                    for(int i = 0; i < quantity; i++)
                    {
                        player.AddItemToInventory(World.ItemByID(id));
                    }
                }

                foreach(XmlNode node in playerData.SelectNodes("/Player/PlayerQuests/PlayerQuest"))
                {
                    int id = Convert.ToInt32(node.Attributes["ID"].Value);
                    bool isCompleted = Convert.ToBoolean(node.Attributes["IsCompleted"].Value);

                    PlayerQuest playerQuest = new PlayerQuest(World.QuestByID(id));
                    playerQuest.IsCompleted = isCompleted;

                    player.Quests.Add(playerQuest);
                }

                return player;
            }
            catch
            {
                // If there was an error with the XML data, return a default player object
                return Player.CreateDefaultPlayer();
            }
        }

        public bool HasRequiredItemToEnterThisLocation(Location location)
        {
            if(location.ItemRequiredToEnter == null)
            {
                // There is no required item for this location, so return "true"
                return true;
            }

            // See if the player has the required item in their inventory
            return Inventory.Exists(ii => ii.Details.ID == location.ItemRequiredToEnter.ID);
        }

        public bool HasThisQuest(Quest quest)
        {
            return Quests.Exists(pq => pq.Details.ID == quest.ID);
        }

        public bool CompletedThisQuest(Quest quest)
        {
            foreach(PlayerQuest playerQuest in Quests)
            {
                if(playerQuest.Details.ID == quest.ID)
                {
                    return playerQuest.IsCompleted;
                }
            }

            return false;
        }

        public bool HasAllQuestCompletionItems(Quest quest)
        {
            // See if the player has all the items needed to complete the quest here
            foreach(QuestCompletionItem qci in quest.QuestCompletionItems)
            {
                // Check each item in the player's inventory, to see if they have it, and enough of it
                if(!Inventory.Exists(ii => ii.Details.ID == qci.Details.ID && ii.Quantity >= qci.Quantity))
                {
                    return false;
                }
            }

            // If we got here, then the player must have all the required items, and enough of them, to complete the quest.
            return true;
        }

        public void RemoveQuestCompletionItems(Quest quest)
        {
            foreach(QuestCompletionItem qci in quest.QuestCompletionItems)
            {
                InventoryItem item = Inventory.SingleOrDefault(ii => ii.Details.ID == qci.Details.ID);

                if(item != null)
                {
                    // Subtract the quantity from the player's inventory that was needed to complete the quest
                    item.Quantity -= qci.Quantity;
                }
            }
        }

        public void AddItemToInventory(Item itemToAdd)
        {
            InventoryItem item = Inventory.SingleOrDefault(ii => ii.Details.ID == itemToAdd.ID);

            if(item == null)
            {
                // They didn't have the item, so add it to their inventory, with a quantity of 1
                Inventory.Add(new InventoryItem(itemToAdd, 1));
            }
            else
            {
                // They have the item in their inventory, so increase the quantity by one
                item.Quantity++;
            }
        }

        public void MarkQuestCompleted(Quest quest)
        {
            // Find the quest in the player's quest list
            PlayerQuest playerQuest = Quests.SingleOrDefault(pq => pq.Details.ID == quest.ID);

            if(playerQuest != null)
            {
                playerQuest.IsCompleted = true;
            }
        }

        public string ToXmlString()
        {
            XmlDocument playerData = new XmlDocument();

            // Create the top-level XML node
            XmlNode player = playerData.CreateElement("Player");
            playerData.AppendChild(player);

            // Create the "Stats" child node to hold the other player statistics nodes
            XmlNode stats = playerData.CreateElement("Stats");
            player.AppendChild(stats);

            // Create the child nodes for the "Stats" node
            XmlNode currentHitPoints = playerData.CreateElement("CurrentHitPoints");
            currentHitPoints.AppendChild(playerData.CreateTextNode(this.CurrentHitPoints.ToString()));
            stats.AppendChild(currentHitPoints);

            XmlNode maximumHitPoints = playerData.CreateElement("MaximumHitPoints");
            maximumHitPoints.AppendChild(playerData.CreateTextNode(this.MaximumHitPoints.ToString()));
            stats.AppendChild(maximumHitPoints);

            XmlNode gold = playerData.CreateElement("Gold");
            gold.AppendChild(playerData.CreateTextNode(this.Gold.ToString()));
            stats.AppendChild(gold);

            XmlNode experiencePoints = playerData.CreateElement("ExperiencePoints");
            experiencePoints.AppendChild(playerData.CreateTextNode(this.ExperiencePoints.ToString()));
            stats.AppendChild(experiencePoints);

            XmlNode currentLocation = playerData.CreateElement("CurrentLocation");
            currentLocation.AppendChild(playerData.CreateTextNode(this.CurrentLocation.ID.ToString()));
            stats.AppendChild(currentLocation);

            if(CurrentWeapon != null)
            {
                XmlNode currentWeapon = playerData.CreateElement("CurrentWeapon");
                currentWeapon.AppendChild(playerData.CreateTextNode(this.CurrentWeapon.ID.ToString()));
                stats.AppendChild(currentWeapon);
            }

            // Create the "InventoryItems" child node to hold each InventoryItem node
            XmlNode inventoryItems = playerData.CreateElement("InventoryItems");
            player.AppendChild(inventoryItems);

            // Create an "InventoryItem" node for each item in the player's inventory
            foreach(InventoryItem item in this.Inventory)
            {
                XmlNode inventoryItem = playerData.CreateElement("InventoryItem");

                XmlAttribute idAttribute = playerData.CreateAttribute("ID");
                idAttribute.Value = item.Details.ID.ToString();
                inventoryItem.Attributes.Append(idAttribute);

                XmlAttribute quantityAttribute = playerData.CreateAttribute("Quantity");
                quantityAttribute.Value = item.Quantity.ToString();
                inventoryItem.Attributes.Append(quantityAttribute);

                inventoryItems.AppendChild(inventoryItem);
            }

            // Create the "PlayerQuests" child node to hold each PlayerQuest node
            XmlNode playerQuests = playerData.CreateElement("PlayerQuests");
            player.AppendChild(playerQuests);

            // Create a "PlayerQuest" node for each quest the player has acquired
            foreach(PlayerQuest quest in this.Quests)
            {
                XmlNode playerQuest = playerData.CreateElement("PlayerQuest");

                XmlAttribute idAttribute = playerData.CreateAttribute("ID");
                idAttribute.Value = quest.Details.ID.ToString();
                playerQuest.Attributes.Append(idAttribute);

                XmlAttribute isCompletedAttribute = playerData.CreateAttribute("IsCompleted");
                isCompletedAttribute.Value = quest.IsCompleted.ToString();
                playerQuest.Attributes.Append(isCompletedAttribute);

                playerQuests.AppendChild(playerQuest);
            }

            return playerData.InnerXml; // The XML document, as a string, so we can save the data to disk
        }
    }
}

SuperAdventure.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;

using Engine;

namespace SuperAdventure
{
    public partial class SuperAdventure : Form
    {
        private const string PLAYER_DATA_FILE_NAME = "PlayerData.xml";

        private Player _player;
        private Monster _currentMonster;

        public SuperAdventure()
        {
            InitializeComponent();

            if(File.Exists(PLAYER_DATA_FILE_NAME))
            {
                _player = Player.CreatePlayerFromXmlString(File.ReadAllText(PLAYER_DATA_FILE_NAME));
            }
            else
            {
                _player = Player.CreateDefaultPlayer();
            }

            MoveTo(_player.CurrentLocation);

            UpdatePlayerStats();
        }

        private void btnNorth_Click(object sender, EventArgs e)
        {
            MoveTo(_player.CurrentLocation.LocationToNorth);
        }

        private void btnEast_Click(object sender, EventArgs e)
        {
            MoveTo(_player.CurrentLocation.LocationToEast);
        }

        private void btnSouth_Click(object sender, EventArgs e)
        {
            MoveTo(_player.CurrentLocation.LocationToSouth);
        }

        private void btnWest_Click(object sender, EventArgs e)
        {
            MoveTo(_player.CurrentLocation.LocationToWest);
        }

        private void MoveTo(Location newLocation)
        {
            //Does the location have any required items
            if(!_player.HasRequiredItemToEnterThisLocation(newLocation))
            {
                rtbMessages.Text += "You must have a " + newLocation.ItemRequiredToEnter.Name + " to enter this location." + Environment.NewLine;
                return;
            }

            // Update the player's current location
            _player.CurrentLocation = newLocation;

            // Show/hide available movement buttons
            btnNorth.Visible = (newLocation.LocationToNorth != null);
            btnEast.Visible = (newLocation.LocationToEast != null);
            btnSouth.Visible = (newLocation.LocationToSouth != null);
            btnWest.Visible = (newLocation.LocationToWest != null);

            // Display current location name and description
            rtbLocation.Text = newLocation.Name + Environment.NewLine;
            rtbLocation.Text += newLocation.Description + Environment.NewLine;

            // Completely heal the player
            _player.CurrentHitPoints = _player.MaximumHitPoints;

            // Update Hit Points in UI
            lblHitPoints.Text = _player.CurrentHitPoints.ToString();

            // Does the location have a quest?
            if(newLocation.QuestAvailableHere != null)
            {
                // See if the player already has the quest, and if they've completed it
                bool playerAlreadyHasQuest = _player.HasThisQuest(newLocation.QuestAvailableHere);
                bool playerAlreadyCompletedQuest = _player.CompletedThisQuest(newLocation.QuestAvailableHere);

                // See if the player already has the quest
                if(playerAlreadyHasQuest)
                {
                    // If the player has not completed the quest yet
                    if(!playerAlreadyCompletedQuest)
                    {
                        // See if the player has all the items needed to complete the quest
                        bool playerHasAllItemsToCompleteQuest = _player.HasAllQuestCompletionItems(newLocation.QuestAvailableHere);

                        // The player has all items required to complete the quest
                        if(playerHasAllItemsToCompleteQuest)
                        {
                            // Display message
                            rtbMessages.Text += Environment.NewLine;
                            rtbMessages.Text += "You complete the '" + newLocation.QuestAvailableHere.Name + "' quest." + Environment.NewLine;

                            // Remove quest items from inventory
                            _player.RemoveQuestCompletionItems(newLocation.QuestAvailableHere);

                            // Give quest rewards
                            rtbMessages.Text += "You receive: " + Environment.NewLine;
                            rtbMessages.Text += newLocation.QuestAvailableHere.RewardExperiencePoints.ToString() + " experience points" + Environment.NewLine;
                            rtbMessages.Text += newLocation.QuestAvailableHere.RewardGold.ToString() + " gold" + Environment.NewLine;
                            rtbMessages.Text += newLocation.QuestAvailableHere.RewardItem.Name + Environment.NewLine;
                            rtbMessages.Text += Environment.NewLine;

                            _player.ExperiencePoints += newLocation.QuestAvailableHere.RewardExperiencePoints;
                            _player.Gold += newLocation.QuestAvailableHere.RewardGold;

                            // Add the reward item to the player's inventory
                            _player.AddItemToInventory(newLocation.QuestAvailableHere.RewardItem);

                            // Mark the quest as completed
                            _player.MarkQuestCompleted(newLocation.QuestAvailableHere);
                        }
                    }
                }
                else
                {
                    // The player does not already have the quest

                    // Display the messages
                    rtbMessages.Text += "You receive the " + newLocation.QuestAvailableHere.Name + " quest." + Environment.NewLine;
                    rtbMessages.Text += newLocation.QuestAvailableHere.Description + Environment.NewLine;
                    rtbMessages.Text += "To complete it, return with:" + Environment.NewLine;
                    foreach(QuestCompletionItem qci in newLocation.QuestAvailableHere.QuestCompletionItems)
                    {
                        if(qci.Quantity == 1)
                        {
                            rtbMessages.Text += qci.Quantity.ToString() + " " + qci.Details.Name + Environment.NewLine;
                        }
                        else
                        {
                            rtbMessages.Text += qci.Quantity.ToString() + " " + qci.Details.NamePlural + Environment.NewLine;
                        }
                    }
                    rtbMessages.Text += Environment.NewLine;

                    // Add the quest to the player's quest list
                    _player.Quests.Add(new PlayerQuest(newLocation.QuestAvailableHere));
                }
            }

            // Does the location have a monster?
            if(newLocation.MonsterLivingHere != null)
            {
                rtbMessages.Text += "You see a " + newLocation.MonsterLivingHere.Name + Environment.NewLine;

                // Make a new monster, using the values from the standard monster in the World.Monster list
                Monster standardMonster = World.MonsterByID(newLocation.MonsterLivingHere.ID);

                _currentMonster = new Monster(standardMonster.ID, standardMonster.Name, standardMonster.MaximumDamage,
                    standardMonster.RewardExperiencePoints, standardMonster.RewardGold, standardMonster.CurrentHitPoints, standardMonster.MaximumHitPoints);

                foreach(LootItem lootItem in standardMonster.LootTable)
                {
                    _currentMonster.LootTable.Add(lootItem);
                }

                cboWeapons.Visible = true;
                cboPotions.Visible = true;
                btnUseWeapon.Visible = true;
                btnUsePotion.Visible = true;
            }
            else
            {
                _currentMonster = null;

                cboWeapons.Visible = false;
                cboPotions.Visible = false;
                btnUseWeapon.Visible = false;
                btnUsePotion.Visible = false;
            }

            // Refresh player's stats
            UpdatePlayerStats();

            // Refresh player's inventory list
            UpdateInventoryListInUI();

            // Refresh player's quest list
            UpdateQuestListInUI();

            // Refresh player's weapons combobox
            UpdateWeaponListInUI();

            // Refresh player's potions combobox
            UpdatePotionListInUI();

            ScrollToBottomOfMessages();
        }

        private void UpdatePlayerStats()
        {
            // Refresh player information and inventory controls
            lblHitPoints.Text = _player.CurrentHitPoints.ToString();
            lblGold.Text = _player.Gold.ToString();
            lblExperience.Text = _player.ExperiencePoints.ToString();
            lblLevel.Text = _player.Level.ToString();
        }

        private void UpdateInventoryListInUI()
        {
            dgvInventory.RowHeadersVisible = false;

            dgvInventory.ColumnCount = 2;
            dgvInventory.Columns[0].Name = "Name";
            dgvInventory.Columns[0].Width = 197;
            dgvInventory.Columns[1].Name = "Quantity";

            dgvInventory.Rows.Clear();

            foreach(InventoryItem inventoryItem in _player.Inventory)
            {
                if(inventoryItem.Quantity > 0)
                {
                    dgvInventory.Rows.Add(new[] { inventoryItem.Details.Name, inventoryItem.Quantity.ToString() });
                }
            }
        }

        private void UpdateQuestListInUI()
        {
            dgvQuests.RowHeadersVisible = false;

            dgvQuests.ColumnCount = 2;
            dgvQuests.Columns[0].Name = "Name";
            dgvQuests.Columns[0].Width = 197;
            dgvQuests.Columns[1].Name = "Done?";

            dgvQuests.Rows.Clear();

            foreach(PlayerQuest playerQuest in _player.Quests)
            {
                dgvQuests.Rows.Add(new[] { playerQuest.Details.Name, playerQuest.IsCompleted.ToString() });
            }
        }

        private void UpdateWeaponListInUI()
        {
            List<Weapon> weapons = new List<Weapon>();

            foreach(InventoryItem inventoryItem in _player.Inventory)
            {
                if(inventoryItem.Details is Weapon)
                {
                    if(inventoryItem.Quantity > 0)
                    {
                        weapons.Add((Weapon)inventoryItem.Details);
                    }
                }
            }

            if(weapons.Count == 0)
            {
                // The player doesn't have any weapons, so hide the weapon combobox and "Use" button
                cboWeapons.Visible = false;
                btnUseWeapon.Visible = false;
            }
            else
            {
                cboWeapons.SelectedIndexChanged -= cboWeapons_SelectedIndexChanged;
                cboWeapons.DataSource = weapons;
                cboWeapons.SelectedIndexChanged += cboWeapons_SelectedIndexChanged;
                cboWeapons.DisplayMember = "Name";
                cboWeapons.ValueMember = "ID";

                if(_player.CurrentWeapon != null)
                {
                    cboWeapons.SelectedItem = _player.CurrentWeapon;
                }
                else
                {
                    cboWeapons.SelectedIndex = 0;
                }
            }
        }

        private void UpdatePotionListInUI()
        {
            List<HealingPotion> healingPotions = new List<HealingPotion>();

            foreach(InventoryItem inventoryItem in _player.Inventory)
            {
                if(inventoryItem.Details is HealingPotion)
                {
                    if(inventoryItem.Quantity > 0)
                    {
                        healingPotions.Add((HealingPotion)inventoryItem.Details);
                    }
                }
            }

            if(healingPotions.Count == 0)
            {
                // The player doesn't have any potions, so hide the potion combobox and "Use" button
                cboPotions.Visible = false;
                btnUsePotion.Visible = false;
            }
            else
            {
                cboPotions.DataSource = healingPotions;
                cboPotions.DisplayMember = "Name";
                cboPotions.ValueMember = "ID";

                cboPotions.SelectedIndex = 0;
            }
        }

        private void btnUseWeapon_Click(object sender, EventArgs e)
        {
            // Get the currently selected weapon from the cboWeapons ComboBox
            Weapon currentWeapon = (Weapon)cboWeapons.SelectedItem;

            // Determine the amount of damage to do to the monster
            int damageToMonster = RandomNumberGenerator.NumberBetween(currentWeapon.MinimumDamage, currentWeapon.MaximumDamage);

            // Apply the damage to the monster's CurrentHitPoints
            _currentMonster.CurrentHitPoints -= damageToMonster;

            // Display message
            rtbMessages.Text += "You hit the " + _currentMonster.Name + " for " + damageToMonster.ToString() + " points." + Environment.NewLine;

            // Check if the monster is dead
            if(_currentMonster.CurrentHitPoints <= 0)
            {
                // Monster is dead
                rtbMessages.Text += Environment.NewLine;
                rtbMessages.Text += "You defeated the " + _currentMonster.Name + Environment.NewLine;

                // Give player experience points for killing the monster
                _player.ExperiencePoints += _currentMonster.RewardExperiencePoints;
                rtbMessages.Text += "You receive " + _currentMonster.RewardExperiencePoints.ToString() + " experience points" + Environment.NewLine;

                // Give player gold for killing the monster 
                _player.Gold += _currentMonster.RewardGold;
                rtbMessages.Text += "You receive " + _currentMonster.RewardGold.ToString() + " gold" + Environment.NewLine;

                // Get random loot items from the monster
                List<InventoryItem> lootedItems = new List<InventoryItem>();

                // Add items to the lootedItems list, comparing a random number to the drop percentage
                foreach(LootItem lootItem in _currentMonster.LootTable)
                {
                    if(RandomNumberGenerator.NumberBetween(1, 100) <= lootItem.DropPercentage)
                    {
                        lootedItems.Add(new InventoryItem(lootItem.Details, 1));
                    }
                }

                // If no items were randomly selected, then add the default loot item(s).
                if(lootedItems.Count == 0)
                {
                    foreach(LootItem lootItem in _currentMonster.LootTable)
                    {
                        if(lootItem.IsDefaultItem)
                        {
                            lootedItems.Add(new InventoryItem(lootItem.Details, 1));
                        }
                    }
                }

                // Add the looted items to the player's inventory
                foreach(InventoryItem inventoryItem in lootedItems)
                {
                    _player.AddItemToInventory(inventoryItem.Details);

                    if(inventoryItem.Quantity == 1)
                    {
                        rtbMessages.Text += "You loot " + inventoryItem.Quantity.ToString() + " " + inventoryItem.Details.Name +Environment.NewLine;
                    }
                    else
                    {
                        rtbMessages.Text += "You loot " + inventoryItem.Quantity.ToString() + " " + inventoryItem.Details.NamePlural + Environment.NewLine;
                    }
                }

                UpdatePlayerStats();
                UpdateInventoryListInUI();
                UpdateWeaponListInUI();
                UpdatePotionListInUI();

                // Add a blank line to the messages box, just for appearance.
                rtbMessages.Text += Environment.NewLine;

                // Move player to current location (to heal player and create a new monster to fight)
                MoveTo(_player.CurrentLocation);
            }
            else
            {
                // Monster is still alive

                // Determine the amount of damage the monster does to the player
                int damageToPlayer = RandomNumberGenerator.NumberBetween(0, _currentMonster.MaximumDamage);

                // Display message
                rtbMessages.Text += "The " + _currentMonster.Name + " did " + damageToPlayer.ToString() + " points of damage." + Environment.NewLine;

                // Subtract damage from player
                _player.CurrentHitPoints -= damageToPlayer;

                // Refresh player data in UI
                lblHitPoints.Text = _player.CurrentHitPoints.ToString();

                if(_player.CurrentHitPoints <= 0)
                {
                    // Display message
                    rtbMessages.Text += "The " + _currentMonster.Name + " killed you." + Environment.NewLine;

                    // Move player to "Home"
                    MoveTo(World.LocationByID(World.LOCATION_ID_HOME));
                }
            }

            ScrollToBottomOfMessages();
        }

        private void btnUsePotion_Click(object sender, EventArgs e)
        {
            // Get the currently selected potion from the combobox
            HealingPotion potion = (HealingPotion)cboPotions.SelectedItem;

            // Add healing amount to the player's current hit points
            _player.CurrentHitPoints = (_player.CurrentHitPoints + potion.AmountToHeal);

            // CurrentHitPoints cannot exceed player's MaximumHitPoints
            if(_player.CurrentHitPoints > _player.MaximumHitPoints)
            {
                _player.CurrentHitPoints = _player.MaximumHitPoints;
            }

            // Remove the potion from the player's inventory
            foreach(InventoryItem ii in _player.Inventory)
            {
                if(ii.Details.ID == potion.ID)
                {
                    ii.Quantity--;
                    break;
                }
            }

            // Display message
            rtbMessages.Text += "You drink a " + potion.Name + Environment.NewLine;

            // Monster gets their turn to attack

            // Determine the amount of damage the monster does to the player
            int damageToPlayer = RandomNumberGenerator.NumberBetween(0, _currentMonster.MaximumDamage);

            // Display message
            rtbMessages.Text += "The " + _currentMonster.Name + " did " + damageToPlayer.ToString() + " points of damage." + Environment.NewLine;

            // Subtract damage from player
            _player.CurrentHitPoints -= damageToPlayer;

            if(_player.CurrentHitPoints <= 0)
            {
                // Display message
                rtbMessages.Text += "The " + _currentMonster.Name + " killed you." + Environment.NewLine;

                // Move player to "Home"
                MoveTo(World.LocationByID(World.LOCATION_ID_HOME));
            }

            // Refresh player data in UI
            lblHitPoints.Text = _player.CurrentHitPoints.ToString();
            UpdateInventoryListInUI();
            UpdatePotionListInUI();

            ScrollToBottomOfMessages();
        }

        private void ScrollToBottomOfMessages()
        {
            rtbMessages.SelectionStart = rtbMessages.Text.Length;
            rtbMessages.ScrollToCaret();
        }

        private void SuperAdventure_FormClosing(object sender, FormClosingEventArgs e)
        {
            File.WriteAllText(PLAYER_DATA_FILE_NAME, _player.ToXmlString());
        }

        private void cboWeapons_SelectedIndexChanged(object sender, EventArgs e)
        {
            _player.CurrentWeapon = (Weapon)cboWeapons.SelectedItem;
        }
    }
}