C# structures/classes/lists index

Question

I'm currently learning C# and I was asked to make a game like monopoly on C and another version on C#. But there's some stuff I don't really understand on C# mainly because it's an object oriented language. So the question is, to manage the players I created a struct on the C version.

typedef struct regist
{
int number;
char name[50];
int money;
int position;
int inGame;
} Player;

Player players[8];

and to get any data of the struct I just do:

players[5].name = "Joe";

Now, my problem with C# is I managed to create the "struct". First I created a struct. Then I tried to make it with a list of structs. Then I just decided to make new instances of a class for every player. I was told it was the best way so I did it. So I have on my player class:

public class Players
{
 int number;
 string name;
 int money;
 int position;
 bool inGame;
 }

and on my form1:

private void newGameButton_Click(object sender, EventArgs e) { setNames(); getNames(); }

    public void setNames()
    {
        Players player1 = new Players();
        player1.name= textBox1.Text;
        Players player2 = new Players();
        player2.name = textBox2.Text;
        Players player3 = new Players();
        player3.name = textBox3.Text;
        Players player4 = new Players();
        player4.name = textBox4.Text;
    }

now what I don't know how to do is:

    public string getNames(){
        return Players[2].name;
    }

How can I achieve this? I also tried with lists but it wouldn't let me do it the way I wanted and also, I want to be able to use this same instances in others classes, I hope that is possible... Thank you.

Please show what you tried with lists. Because that's one of the bests ways to go. And by the way your final snippet won't work because a char array is not a string and your field is private by default. — Pierre-Luc Pineault, Jan 22 '15 at 18:54
what getNames should do? You are creating a class which is good, and creating multiple instances of it by calling new operator, which is also good. However there is a little typo in your example code: player2.name... <=> jogador2.name = textBox2.Text; Also change class name from Players to Player so its correctly named. — Panu Oksala, Jan 22 '15 at 18:55
@MPT Did you look at your C# code snippet? You have a char array in your class. And all those fields are private. — Pierre-Luc Pineault, Jan 22 '15 at 18:58
@Mino I'm sorry, it's fixed now, the typo was because I changed the code was in portuguese (jogadores) and i changed it to english (players) and forgot to change those :p — MPT, Jan 22 '15 at 18:59
@Pierre-LucPineault Oh, I got it now...just a typo, because to post on the forum I copied from the C part, it's of course a string in my code, though :) — MPT, Jan 22 '15 at 19:00

score 2 · Accepted Answer · answered Jan 22 '15 at 19:04

2

Once you have a List<Players>, you need to actually add your intances to the list.Then you can index as you expect:

private List<Players> allPlayers = new List<Players>();

public void setNames()
{
    Players player1 = new Players();
    player1.name= textBox1.Text;
    Players player2 = new Players();
    player2.name = textBox2.Text;
    Players player3 = new Players();
    player3.name = textBox3.Text;
    Players player4 = new Players();
    player4.name = textBox4.Text;

    allPlayers.Add(player1);
    allPlayers.Add(player2);
    allPlayers.Add(player3);
    allPlayers.Add(player4);
}

Now you can access it as allPlayers[2] or whatever other index, in your other code.

A style note, your class should be named Player not Players. A Player is an object, Players indicates a collection property of Player objects.

answered Jan 22 '15 at 19:04

BradleyDotNET

60,462
10
96
117

yes, I get that and thank you but my question is, how can I then do that allPlayers[2] from within other classes? do I have to instantiate a new instance of the class that code is in? – MPT Jan 22 '15 at 19:07
@MPT No, you would need to pass the `allPlayers` list to that object, either on the class's constructor or as a parameter to one of the methods. – BradleyDotNET Jan 22 '15 at 19:08
Presumably you know how parameters work, so your other class would have a method, say the constructor, that accepts a `List`, ie: `public MyOtherClass(List players)`. It would then probably store that reference off in a private variable, that the classes methods could then access. Objects are always passed **as** a reference (like a pointer) in C#, so both your variable and the other classes variable will point to the same object. – BradleyDotNET Jan 22 '15 at 19:21
@MPT Not a problem, glad to help! – BradleyDotNET Jan 22 '15 at 22:29

vishu9219 · Answer 2 · 2015-01-22T19:37:38.473

0

While Creating class use properties

public class Players
{
    public int number{get;set;}
    public string name{get;set;}
    public int money{get;set;}
    public int position { get; set; }
    public bool inGame { get; set; }

    public string getNames(){
    return name;
    }
}

and while creating its objects

public  Players[] p = new Players[5];

and assignment can be done

p[0].name = textBox1.Text;
p[1].name = textBox2.Text;
p[2].name = textBox3.Text;
p[3].name = textBox4.Text;
p[4].name = textBox5.Text;

now if from any place of object p is accessible the for sure you can

 p[2].getNames();

do this.

OR

use List

List<Players> pList = new List<Players>();
Players p1 = new Players();
p1.name="abc";
pList.add(p1);
Players p2 = new Players();
p2.name="xyz";
pList.add(p2);

and again if pList is accessible then

public string getNames(){
return pList[0].name;
}

edited Jan 22 '15 at 19:37

answered Jan 22 '15 at 19:13

vishu9219

761
6
14

when I use the return it says "index out of range", but if I put an messageBox.Show it works ok, why? – MPT Jan 22 '15 at 19:22
do one thing create a function getName inside the class and call using p[2].getName(); Hope this will solve your problem. – vishu9219 Jan 22 '15 at 19:25
http://stackoverflow.com/questions/4142867/what-is-difference-between-property-and-variable-in-c-sharp – vishu9219 Jan 22 '15 at 19:36
Arrays start at index 0, you might want to fix that. – Chris Jan 22 '15 at 19:36

C# structures/classes/lists index

2 Answers2