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Bind a linkedlist to a datagridview

I'm trying to bind a linkedlist to a datagridview. The method below works for the properties in the class except the array.
If I declare the array as a new instance the linkedlist is created correctly, but the array is not bound into the datagridview.
If the array is created as a property (I think the code is correct) causes An unhandled exception of type 'System.StackOverflowException' occurred when the linkedlist is created.
Thanks for any help.
public class PayoffNode
{
public int DealNo { get; set; }
public string Category { get; set; }
public string Strategy { get; set; }
public string GreekType { get; set; }
// declare array as instance or as a property?
//public double[] Data = new double[22];
public double[] Data
{
get { return Data; }
set { Data = value; }
}
}
LinkedList<Globals.PayoffNode> PayLL = new LinkedList<Globals.PayoffNode>();
Random Rnd = new Random();
for (int K = 1; K <= 10; K++)
{
var T = new Globals.PayoffNode();
T.Category = "Account==" + K;
T.GreekType = "Greek==" + K;
T.DealNo = K;
T.Strategy = "Strategy==" + K;
for (int DP = 1; DP <= 21; DP++)
{
T.Data[DP] = Rnd.Next(10, 99);
}
PayLL.AddLast(T);
}
List<Globals.PayoffNode> qP = (from P in PayLL
where P.Category == "Account==4" && P.DealNo == 4 && P.GreekType == "Greek==4" && P.Strategy == "Strategy==4"
select P).ToList();
PayoffTable.DataSource = qP;
Update:
Thanks for the comments, this seems to be working.
public class PayoffNode
{
public int DealNo { get; set; }
public string Category { get; set; }
public string Strategy { get; set; }
public string GreekType { get; set; }
public double Data1 { get; set; }
public double Data2 { get; set; }
public double Data3 { get; set; }
public double[] Data = new double[22];
}
LinkedList<Globals.PayoffNode> PayLL = new LinkedList<Globals.PayoffNode>();
Random Rnd = new Random();
for (int K = 1; K <= 10; K++)
{
var T = new Globals.PayoffNode();
T.Category = "Account==" + K;
T.GreekType = "Greek==" + K;
T.DealNo = K;
T.Strategy = "Strategy==" + K;
for (int DP = 1; DP <= 21; DP++)
{
T.Data[DP] = Rnd.Next(10, 99);
}
PayLL.AddLast(T);
}
List<Globals.PayoffNode> qP = (from P in PayLL
where P.Category == "Account==4" && P.DealNo == 4 && P.GreekType == "Greek==4" && P.Strategy == "Strategy==4"
select new Globals.PayoffNode()
{
Category=P.Category,
DealNo=P.DealNo,
GreekType=P.GreekType,
Strategy=P.Strategy,
Data1=P.Data[1],
Data2 = P.Data[2],
Data3 = P.Data[3],
}).ToList();
PayoffTable.DataSource = qP;

One way to avoid making 21 Data properties is to convert the List to DataTable:
class PayoffNode
{
public int DealNo;
public string Category;
public double[] Data; // = new double[21];
}
and then
Random Rnd = new Random();
List<PayoffNode> PayLL = Enumerable.Range(1, 10).Select(i => new PayoffNode {
DealNo = i,
Category = "Account==" + i,
Data = Enumerable.Range(1, 21).Select(d => (double)Rnd.Next(10, 99)).ToArray()
}).ToList();
// List<PayoffNode> to DataTable
var dt = new DataTable();
dt.Columns.Add("DealNo", typeof(int));
dt.Columns.Add("Category"); // typeof(string) by default
for (int i = 1; i <= 21; i++)
dt.Columns.Add("Data" + i, typeof(double));
foreach (var P in PayLL)
{
var dr = dt.Rows.Add(P.DealNo, P.Category);
for (int i = 0; i < 21; i++)
dr[i+2] = P.Data[i]; // +2 is the number of fields before the Data fields
}
PayoffTable.DataSource = dt;
dt.DefaultView.RowFilter = " Category = 'Account==4' ";
The advantage is that you set the DataSource only once and just change the RowFilter to filter it. Also, any changes made in the DataGridView change the DataTable and vice-versa.
Note that arrays in C# and most other languages start from 0 and not from 1 ( .Data[0] to access the first item in the array ), so the for loop to access the Data array in my example is from 0 to 20.

public double[] Data
{
get { return Data; }
set { Data = value; }
}
This is the problem, the object in the set and get method needs to refer to a different object otherwise whenever the object value is set or trying to be retrieved it will just keep calling these methods infinitely. should be...
private double[] _data;
public double[] Data
{
get { return _data; }
set { _data = value; }
}
or...
public double[] Data { get; set; }

list class property in a class c# assign value

class Program
{
static void Main(string[] args)
{
Posting onjPosting = null;
List<Posting> objList = null;
for (int i = 0; i < 100; i++)
{
onjPosting = new Posting();
onjPosting.Key1 = i;
for (int j = 0; j < 5; i++)
{
Choice objChoice = new Choice();
objChoice.ID = i;
objChoice.VAL = j;
onjPosting.GetPostingChoice.Add(objChoice); // GETTING ERROR [ Object reference not set to an instance of an object. ]
}
objList.Add(onjPosting);
}
}
}
public class Choice
{
public int ID { get; set; }
public int VAL { get; set; }
}
public class Posting
{
public int Key1 { get; set; }
public List<Choice> GetPostingChoice { get; set; }
}
While looping through and assigning the value I am getting error . How to solve this ? Please help me out .
My requirement is one parent class (Posting) , can contain number of data List .
Thanks in advance .

You never allocate the GetPostingChoice list so of course it is null.
You could do it in the constructor:
public class Posting
{
public Posting()
{
GetPostingChoice = new List<Choice>();
}
public int Key1 { get; set; }
public List<Choice> GetPostingChoice { get; set; }
}

Add a public constructor on your Posting class:
public class Posting
{
public int Key1 { get; set; }
public List<Choice> GetPostingChoice { get; set; }
public Posting()
{
GetPostingChoice = new List<Choice>();
}
}
You also have other errors:
You do not initialize objList, so you cannot add in there.
List<Posting> objList = null;
So you will get another Null Reference when you get to:
List<Posting> objList = null;
In your second loop you increase i instead of j so it will never end.
for (int j = 0; j < 5; i++)
This is how it should look:
Posting onjPosting = null;
List<Posting> objList = new List<Posting>();
for (int i = 0; i < 1; i++)
{
onjPosting = new Posting();
onjPosting.Key1 = i;
for (int j = 0; j < 5; j++)
{
Choice objChoice = new Choice();
objChoice.ID = i;
objChoice.VAL = j;
onjPosting.GetPostingChoice.Add(objChoice); // GETTING ERROR [ Object reference not set to an instance of an object. ]
}
objList.Add(onjPosting);
}
Since you ask for another approach, and this is just one of the many ways you could do it, have a look at this:
List<Posting> objList = new List<Posting>();
Enumerable.Range(0,100)
.Select
(
(x,i)=>new Posting
{
Key1 = i,
GetPostingChoice = Enumerable.Range(0,5).Select((p,j)=>new Choice{ID = i,VAL = j}).ToList()
}
);

Add child to class properties in for cycle

I have a problems with adding subelements off AddressElement objects
My test class:
public class AddressElement
{
public AddressElement[] AddressElement1 { get; set; }
public string PostIndex { get; set; }
}
My test interface:
public interface IAddress
{
string PostIndex { get; }
}
private AddressElement CreateAddressElement(IAddress address)
{
return new AddressElement
{
PostIndex = address.PostIndex
};
}
private int startIndex = 0;
private int finalIndex = 5;
Get elements method:
private AddressElement[] GetAddressElements(List addresses, int startIndex, int finalIndex)
{
List addressElements = new List();
for (int i = startIndex; i < finalIndex; i++)
{
if (i == startIndex)
{
addressElements.Add(CreateAddressElement(addresses[i]));
if (i != startIndex )
{
AddressElement addressElement = addressElements[startIndex];
addressElements[startIndex].AddressElement1 = new[] { CreateAddressElement(addresses[i]) };
}
I need add all subelements of AddressElement in for cycle: addressElements[startIndex].AddressElement1[startIndex].AddressElement1[startIndex].AddressElement1[startIndex].AddressElement1[startIndex]....

You can do this by using Linq :
private AddressElement[] GetAddressElements(List addresses, int startIndex, int finalIndex) {
return addresses.Skip(startIndex).Take(finalIndex - startIndex).Select(s => CreateAddressElement(s)).ToArray() ;
}
Hope it will help you.

Adding data to a list inside a class

I want to fill a list<int> inside a class I can't get it to work.
(Some / Most of the code is from here
The class:
class Fiu
{
public int feleseg { get; set; }
public List<int> preferencia { get; set; }
public Fiu (int _feleseg) : this()
{
feleseg = _feleseg;
}
public Fiu()
{
this.preferencia = new List<int>();
}
}
The code:
for (int i = 1; i < 4; i++)
{
Fiu ujfiu = new Fiu(0);
for (int j = 1; j < 4; j++)
{
ujfiu.preferencia[j-1] = 1;
}
}
The main goal would be filling it from excel, but right now it doesn't even put 1-s in. I don't know what's wrong.
I get a "Argument out of range exception unhandled" error.

Replace This:
ujfiu.preferencia[j-1] = 1;
With This:
ujfiu.preferencia.Add(1);

Give an Array a Value

I am trying to make a game where an image appears, and if it is not clicked the image should disappear. I need help giving my array a value of three, then subtract it in another method.
Code:
NameCount = -1;
NameCount++;
Grid.SetColumn(mole, ranCol);
Grid.SetRow(mole, ranRow);
grid_Main.Children.Add(mole);
for (int i = 0; i < NumofImages; i++)
{
//Where I must give a value to the array of the array to 3 for every image that appears.
}
//Where I am trying to make the image disappear after 3 seconds.
private void deleteMole()
{
NumofImages = TUtils.GetIniInt(Moleini, "NumPictures", "pictures", 8);
NumberofImages = Convert.ToInt32(NumofImages);
for (int j = 0; j < NumofImages; j++)
{
CounterArray[j]--;
if (CounterArray[j] == 0)
{
//Not Sure How to delete image
Thanks for the help!

You could keep track of the images in another array.
After you add the image to the view you should also add it to the array:
images[j] = mole;
Then later:
if (CounterArray[j] == 0)
{
grid_Main.Children.Remove(images[j]);
}
But using static arrays and separating data is not a good idea.
If you can you should better aggregate all the metadata and the image together in the same structure:
class Mole
{
public int Counter { get; set; }
public Control Image { get; set; }
}
and manage them in a single List<Mole>; adding and removing them will be simpler.
Here is some code that illustrates the idea (won't compile):
class Mole
{
public int X { get; set; }
public int Y { get; set; }
public int Counter { get; set; }
public Control Image { get; set; }
public bool IsNew { get; set; }
}
class Test
{
IList<Mole> moles = new List<Mole>();
private static void AddSomeMoles()
{
moles.Add(new Mole{ X = rand.Next(100), Y = rand.Next(100), Counter = 3, Image = new PictureBox(), IsNew = true });
}
private static void DisplayMoles()
{
foreach (Mole mole in moles)
{
if (mole.IsNew)
{
grid_Main.Children.Add(mole.Image);
mole.IsNew = false;
}
}
}
private static void CleanupMoles()
{
foreach (Mole mole in moles)
{
mole.Counter -= 1;
if (mole.Counter <= 0)
{
grid_Main.Children.Remove(mole.Image);
moles.Remove(mole);
}
}
}
static void Main()
{
while (true)
{
AddSomeMoles();
DisplayMoles();
Thread.Sleep(1000);
CleanupMoles();
}
}
}

If you want to give every element in a List a certain value, use a foreach loop. In this case, it would look like:
foreach(int currentElement in CounterArray)
{
currentElement = 3;
}
This will loop through each element of the List and set it to 3.
EDIT: If you're using an array, which you are, you would do the following:
for (int i = 0; i < CounterArray.Length; i++)
{
CounterArray[i] = 3;
}