Initilialising an array of objects that contain an array of other objects? - c#

I am trying to declare an array of buildings but the floors associated with each building are never initialised. I want to provide values to the data members for each instance of floor that is associated with each instance of building:
class Floor
{
public int number;
public int rooms;
//constructor
Floor()
{
rooms = 5;
number= 0;
}
}
class Building
{
public Floor[] floors= new Floor[6];
}
public partial class frmF2 : Form
{
Building[] x = new Building[7];
...
}

But it is very ugly.
class Building
{
Building()
{
floors = new Floor[6];
for(int i=0; i<6;++i)
floors[i] = new Floor();
}
public Floor[] floors;
}

Related

How to check property value of object

i want do some action if value of property in object is equal something.
My object:
//abstract class Tile.cs
namespace DungeonGame.Tiles
{
public abstract class Tile
{
public abstract string Type { get; set; }
}
}
//Item.cs that iherits from Tile.cs
namespace DungeonGame
{
public class Item : Tile
{
public override string Type { get; set; }
public string Name { get; set; }
public Item(string name)
{
this.Type = "item";
this.Name = name;
}
}
}
And i have several objects in public Object[,] BoardTiles { get; private set; }, I had to store different types of tiles in same place so i had to use Object type array.
What i'm trying to do is replace array index with different type of object, depending of the value of property (In this case I set value depending of object type not his value of property):
public void movefillRight(int playerPositionRowIndex, int playerPositionColumnIndex)
{
for (int r = 0; r < Rows; r++)
{
for (int c = 0; c < Cols; c++)
{
if (BoardTiles[playerPositionRowIndex, playerPositionColumnIndex ].GetType().ToString() == ("DungeonGame.Item"))
{
/* placePlayerOnTheBoard(playerPositionRowIndex, playerPositionColumnIndex, PlayerTile);
*/ BoardTiles[playerPositionRowIndex, playerPositionColumnIndex] = Item1;
BoardTiles[playerPositionRowIndex, playerPositionColumnIndex - 1] = Floor;
}
else if (BoardTiles[playerPositionRowIndex, playerPositionColumnIndex-1].GetType().ToString() == ("DungeonGame.Item"))
{
BoardTiles[playerPositionRowIndex, playerPositionColumnIndex-1] = Item1;
placePlayerOnTheBoard(playerPositionRowIndex, playerPositionColumnIndex, PlayerTile);
}
else
{
placePlayerOnTheBoard(playerPositionRowIndex, playerPositionColumnIndex, PlayerTile);
BoardTiles[playerPositionRowIndex, playerPositionColumnIndex - 1] = Floor;
}
}
}
Console.WriteLine(BoardTiles[playerPositionRowIndex, playerPositionColumnIndex].GetType().ToString());//log
}
The functionality of the function is to leave the same object on the same index when the player walks over it, so the problem is that code is ok when I have one Item, for example only sword, but when there are more items i can replace index always with same object but not with object witch different properties, when the player walks over a good sword and bad sword (same object, but another properties) he leave behind just sword... I have idea how to solve this problem but i need to refer to property value which is at specific index of my object array.
After you check that the item in the array is of a specific type you can then cast it.
if (BoardTiles[playerPositionRowIndex, playerPositionColumnIndex ].GetType().ToString() == ("DungeonGame.Item"))
{
var item = (DungeonGame.Item)BoardTiles[playerPositionRowIndex, playerPositionColumnIndex];
Console.Writeline(item.Name);
}

Confusion over using abstract class in c#

I have a question since I'm new in programming Im really confused about how to implement a best practice solution for the following problem, Its a game logic,here are the possible ways of making points
EnemyA 400,
EnemyB 500,
EnemyC 700,
Coin 200,
FireBall 300
means hitting Coin gives you 200 points and shooting FireBall gives you 300 &...
if you reach 1000 points you will get an extra life, the logic simple but implementing the best practice is not(at least to me)should I use abstract class or Dictionary?
So far, I used a Dictionary, I read a given file (txt) file which is written (EnemyA,EnemyB,Coin,Coin,Coin,Coin) then I calculate the points:
public int pointCal(IEnumerable<string> enemyType)
{
var possiblePoints = new Dictionary< EnemisEntity,int>()
{
{new EnemisEntity{enemyType="EnemyA"},400 },
{new EnemisEntity{enemyType="EnemyB" },500 },
{new EnemisEntity{enemyType="EnemyC"},700 },
{new EnemisEntity{enemyType="Fireball"},300 },
{new EnemisEntity{enemyType="Coin"},200 },
};
int z=0;
List<int> myPoints=new List<int> ();
foreach (var item in enemyType)
{
z = possiblePoints.FirstOrDefault(f => f.Key.enemyType.Equals(item)).Value;
myPoints.Add(z);
}
int finalPonts= g.Sum(s=>Convert.ToInt32(s));
return finalPonts;
}
Enemy entity class:
public class EnemisEntity
{
public string enemyType { get; set; }
}
It depends. Are the enemies different types of objects (with different properties and such)?
Then it might make sense to create an abstract class and child classes.
public abstract class Shootable {
public int points;
}
public class EnemyA: Shootable {
}
public class EnemyB: Shootable {
}
public class Coin: Shootable {
}
// etc
If all your items are just shootable with one description, then
public class Shootable {
public int points { get; set; }
public string enemyType { get; set; }
public Shootable(int points, string enemyType ){
this.points = points;
this.enemyType = enemyType;
}
}
// then create like
var coin = new Shootable(500, "coin");
If all enemies can be modeled in the same class, then you only need shootable class
Then get the points:
IEnumerble<Shootable> shootableItems = GetShootableFromFile();
var score = shootableItems.Sum(s => s.Points);
You GetShootableFromFile should create one object per file row. So it is a viable situation to create the same objects twice:
// This is a mock to indicate multiple instances of the same class.
public IEnumerble<Shootable> GetShootableFromFile() {
List<Shootable> shootable = new List<Shootable>();
shootable.Add(new Shootable(500,"coin"));
shootable.Add(new Shootable(500,"coin"));
shootable.Add(new Shootable(500,"coin"));
shootable.Add(new Shootable(300,"enemyA"));
shootable.Add(new Shootable(300,"enemyB"));
// etc
}
To me, this is a question of design. When the only difference between enemies is just the value of points as well as their name it is not a good idea to define a class hierarchy. The only thing different between a EnemyA and a EnemyB class would be just the values contained within each class. So you can use a single common class to hold information for each enemy and process the points.
Below is the simplest working prototype that I could code that implements this design. It relies on two classes. The EnemyEntity class to hold the type of enemy and its points, and a Game class that contains the logic behind scoring and keeping a record of all possible enemies.
public class EnemyEntity
{
public EnemyEntity(string type, int points)
{
Type=type;
Points=points;
}
public string Type { get; }
public int Points { get; }
}
public class Game
{
public Game(params (string type, int points)[] values)
{
this.Enemies = new List<EnemyEntity>();
foreach (var (type, points) in values)
{
Enemies.Add(new EnemyEntity(type, points));
}
}
public List<EnemyEntity> Enemies { get; }
public int CalculatePoints(IEnumerable<string> targets)
{
int points = 0;
foreach (var item in targets)
{
var target = Enemies.FirstOrDefault((enemy) => enemy.Type.Equals(item));
if (target!=null)
{
points+= target.Points;
}
}
return points;
}
}
class Program
{
static void Main(string[] args)
{
var game = new Game(
("EnemyA", 400),
("EnemyB", 500),
("EnemyC", 700),
("Coin", 200),
("FireBall", 300));
var input = "EnemyA,EnemyB,Coin,Coin,Coin,Coin";
var targets = input.Split(',');
var points = game.CalculatePoints(targets);
Console.WriteLine(points);
// 1700
}
}
NOTES:
The simplest approach is to use a List<EnemyEntity> and do the lookup with .FirstOrDefault(). I could use a Dictionary<string,EnemyEntity> which would simplify the lookup process. Here is how the Game class would change using a dictionary.
public class Game
{
public Game(params (string type, int points)[] values)
{
this.Enemies = new Dictionary<string, EnemyEntity>();
foreach (var (type, points) in values)
{
Enemies[type] = new EnemyEntity(type, points);
}
}
public Dictionary<string, EnemyEntity> Enemies { get; }
public int CalculatePoints(IEnumerable<string> targets)
{
int points = 0;
foreach (var item in targets)
{
var target = Enemies[item];
if (target!=null)
{
points+= target.Points;
}
}
return points;
}
}

Creating list/array of class instances?

I'm fairly new to C# and I have just learned about creating custom classes. The problem is, I can't figure out how to take the 40~65 instances of this class and put them in a list/array (whichever one I need) where I can locate and choose one based on an attribute defined in it.
Here's the class I have created right now:
public class Team
{
protected int teamNum;
protected double averageMatchPoints;
protected string location;
protected int matchesPlayed;
protected int matchesPending;
protected int blowouts;
//Team Number
public void SetNumber(int num)
{
teamNum = num;
}
public int GetNumber()
{
return teamNum;
}
//Average Points per match
public void AverageMatchPoints(double p)
{
averageMatchPoints = p;
}
public double GetAverageMatchPoints()
{
return averageMatchPoints;
}
//location information
public void SetLocation(string l)
{
location = l;
}
public string GetLocation()
{
return location;
}
//Number of Played Matches
public void PlayedMatches(int mat)
{
matchesPlayed = mat;
}
public int GetPlayedMatches()
{
return matchesPlayed;
}
//Number of matches pending (not played)
public void PendingMatches(int pen)
{
matchesPending = pen;
}
public int GetPendingMatches()
{
return matchesPending;
}
//Number of Blowouts (matches where the robot was disbaled for any number of reasons)
public void SetBlowouts(int b)
{
blowouts = b;
}
public int GetBlowouts()
{
return blowouts;
}
}
Now, if I had 40~65 of these teams competing at an event and I made an instance of this class for each one, how would I populate a combobox with each team number (teamNum) and then locate one specific team out of all the instances in the program by their team numbers?
I recommend a dictionary!
// Declared somewhere
private Dictionary<int, Team> _teamDictionary = new Dictionary<int, Team>();
.
.
.
//Initialization code - I assume you have gotten your teams from a database or somewhere?
foreach (var team in myTeamsList)
{
_teamDictionary.Add(team.teamNum, team);
}
.
.
.
// Later when you want to locate a team:
var team = _teamDictionary[selectedTeamNum];
Have you tried creating a List yet?
List<Team> Teams { get; set; }
You can then bind your combobox to the list/collection/IEnumerable of all the teams that you have. To initialize the teams up to 40/60 do the following?
for(int i = 0; i < 60; i++)
{
Team t = new Team();
t.Name = "Team 1";
t.TeamNumber = i + 1;
Teams.Add(t);
}
List<Team> allTheTeams = new List<Team>();
for(var i = 0; i < 65; i++){
allTheTeams.Add(new Team { teamNum = i });
}
And to get the team with number 34:
allTheTeams.FirstOrDefault(x => x.teamNum == 34);
Like this:
Add a constructor to your class that takes the teamnumber:
(this is the best solution if every team needs to have a number. So you can not forget to set the team number as you can not create an object of type team without setting the number in the constructor)
public class Team
{
protected int _teamNum;
public Team(int teamNum)
{
_teamNum = teamNum;
}
public int getTeamNum()
{
return _teamNum;
}
//more logic
}
Populate a dictionary, the comboBox and get a team for its number:
Dictionary<int, Team> dictionary = new Dictionary<int, Team>();
int teamNum = 1;
// Add your Teams to a dictionary (example)
dictionary.Add(teamNum ,new Team(teamNum++));
dictionary.Add(teamNum, new Team(teamNum++));
dictionary.Add(teamNum, new Team(teamNum++));
// Populate a comboBox
foreach(KeyValuePair<int,Team> kvp in dictionary)
{
comboBox1.Items.Add(kvp.Value.getTeamNum().ToString());
}
// get a team for a given teamNumer
int targetTeamNumber = 2;
if (dictionary.ContainsKey(targetTeamNumber))
{
Team team = dictionary[targetTeamNumber];
// do something with the team
}

how can i get an access to the elements of array in the class

I have a problem which I don't know how to solve. I have a class. This class has two arrays. I would like to get access via properties. How can I do it? I tried to use indexers, but it is possible if I have only one array. Here what I want to do:
public class pointCollection
{
string[] myX;
double[] myY;
int maxArray;
int i;
public pointCollection(int maxArray)
{
this.maxArray = maxArray;
this.myX = new string[maxArray];
this.myY = new double[maxArray];
}
public string X //It is just simple variable
{
set { this.myX[i] = value; }
get { return this.myX[i]; }
}
public double Y //it's too
{
set { this.myY[i] = value; }
get { return this.myY[i]; }
}
}
With this code, my X and Y are only simple variables, but not arrays.
If I use indexers, I get access only to one array:
public string this[int i]
{
set { this.myX[i] = value; }
get { return this.myX[i]; }
}
But how can I get access to second array?
Or I can't use property in this case? And I need only use:
public string[] myX;
public double[] myY;
An example with Tuples.
public class pointCollection
{
Tuple<String,Double>[] myPoints;
int maxArray;
int i;
public pointCollection(int maxArray)
{
this.maxArray = maxArray;
this.myPoints = new Tuple<String,Double>[maxArray];
}
public Tuple<String,Double> this[int i]
{
set { this.myPoints[i] = value; }
get { return this.myPoints[i]; }
}
}
And to access the points you do...
pointCollection pc = new pointCollection(10);
// add some data
String x = pc[4].Item1; // the first entry in a tuple is accessed via the Item1 property
Double y = pc[4].Item2; // the second entry in a tuple is accessed via the Item2 property
If I got it right, you need some kind or read/write-only wrapper for arrays to be exposed as properties.
public class ReadWriteOnlyArray<T>{
private T[] _array;
public ReadWriteOnlyArray(T[] array){
this._array = array;
}
public T this[int i]{
get { return _array[i]; }
set { _array[i] = value; }
}
}
public class pointCollection
{
string[] myX;
double[] myY;
int maxArray;
public ReadWriteOnlyArray<string> X {get; private set;}
public ReadWriteOnlyArray<double> Y {get; private set;}
public pointCollection(int maxArray)
{
this.maxArray = maxArray;
this.myX = new string[maxArray];
this.myY = new double[maxArray];
X = new ReadWriteOnlyArray<string>(myX);
Y = new ReadWriteOnlyArray<double>(myY);
}
}
and usage
var c = new pointCollection(100);
c.X[10] = "hello world";
c.Y[20] = c.Y[30] + c.Y[40];
The closest you'll come without either changing your data structure or moving to methods is to make a property that returns each array, much like you did in your first code block, except without the [i].
Then, you do var x = instanceOfPointCollection.MyX[someI]; for example.

How do I create an array of objects in constructor?

I have two classes:
game
element
I want to be able to define an array of element objects in a game object. When I try this I get the warning message "..is never assigned to, and will always have its default value null"; in the local variables in the debugger I can see that the array exists, but all entries are null. The class Element works as I would expect. If I assign element objects to an array in Main it works, but not when I move the code to the Game constructor.
What am I doing wrong? I'm new to C# so it could be something very basic. Code below. Many thanks.
class Element
{
public Element()
{
elements = new List<int>(3);
elements.Add(1);
elements.Add(2);
elements.Add(3);
}
List<int> elements;
public void PrintElement()
{
for (int i = 0; i < 3; i++)
{
Console.WriteLine("Element {0}: {0}", i + 1, elements[i]);
}
}
}
class Game
{
public Game()
{
Element1 = new Element();
Element2 = new Element();
Element3 = new Element();
Element[] ThisGame = new Element[3];
ThisGame[0]= Element1;
ThisGame[1] = Element2;
ThisGame[2] = Element3;
}
public Element[] ThisGame;
private Element Element1;
private Element Element2;
private Element Element3;
public void PrintGameElement(int number)
{
ThisGame[number].PrintElement();
}
}
class Program
{
Game MyGame;
static void Main(string[] args)
{
Game MyGame = new Game();
MyGame.PrintGameElement(2);
Console.Read();
}
}
In Game, you are re-declaring ThisGame.
Change
Element[] ThisGame = new Element[3];
to
ThisGame = new Element[3];
Your Game constructor should look like this:
public Game()
{
Element1 = new Element();
Element2 = new Element();
Element3 = new Element();
ThisGame = new Element[3];
ThisGame[0]= Element1;
ThisGame[1] = Element2;
ThisGame[2] = Element3;
}
You need to set the list object to something when you initialize it.
List<int> elements = null;
OR
List<int> elements = new List<int>();
look at this code it may help you to make some order in your code:
Element class :
class Element
{
//property on element to save element data
public string ElementData { get; set; }
public Element(string data)
{
ElementData = data;
}
}
Game class :
class Game
{
//property on Game to save all elements
Element[] Elements { get; set; }
public Game(Element[] elements)
{
Elements = elements;
}
public void PrintGameElements()
{
foreach (var element in Elements)
{
Console.WriteLine(element.ElementData);
}
}
public void PrintElement(int index)
{
Console.WriteLine(Elements[index].ElementData);
}
}
Main function that initialize the array and pass it to the game :
static void Main(string[] args)
{
//initialize the array
var elements = new[]
{
new Element("data x"),
new Element("data y"),
new Element("data z")
};
//pass the elements to the game
var game = new Game(elements);
//print the second element
game.PrintElement(1);
//print all elements
game.PrintGameElements();
Console.ReadKey();
}
}

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