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Specific Algorithm in C# for a speed dating [closed]

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The goal is to divide the 50 people into 10 tables. So 5 people per table. Each person has 2 minutes to introduce themselves to the 4 others. Once everyone has introduced themselves, everyone changes tables. And that in 10 rounds. Two people cannot meet twice
Here's the code I have done :
internal class Program
{
private static void Main(string[] args)
{
int biggestNumberOfGroupCreated = 0;
List<Group> biggestGroupes = new List<Group>();
Start:
// Créer une liste de toutes les personnes
List<int> people = new List<int>();
List<Group> groups = new List<Group>();
List<PersonAlreadyUsed> PeopleAlreadyUsed = CreateListPersonAlreadyUsed();
// Generate person name from 1 to 50
for (int i = 0; i < 50; i++)
{
people.Add(i);
}
List<Couple> couples = new();
GenerateCouples(couples);
//Generate 10 rounds
for (int round = 0; round < 10; round++)
{
ResetAlreadyUsedPeople(PeopleAlreadyUsed);
for (int table = 0; table < 9; table++)
{
Group groupe = new();
for (int chair = 0; chair < 5; chair++)
{
if (chair == 0)
{
int randomElement = GetRandomElement(PeopleAlreadyUsed);
groupe.users[chair] = people[randomElement];
Console.WriteLine($"First seated person {people[randomElement]} for round : {round} in table : {table}");
var alreadyUsed = PeopleAlreadyUsed.FirstOrDefault(x => x.Person == randomElement);
alreadyUsed.AlreadyUsed = true;
}
else
{
bool CanBeAdd = false;
int MemoUser = 0;
int u = 0;
int cptInWhileLoop = 0;
while (!CanBeAdd)
{
bool ret = false;
//Check if the new people can be added
for (int c = 0; c < chair; c++)
{
MemoUser = u;
ret = CheckedIfCanBeAdd(u, groupe.users[c], couples);
if (ret == false)
{
break;
}
}
CanBeAdd = ret;
u = GetUnusedPerson(PeopleAlreadyUsed, cptInWhileLoop);
if (u == -1)
{
Console.WriteLine($"All person already used {groups.Count}");
if (groups.Count > biggestNumberOfGroupCreated)
{
biggestNumberOfGroupCreated = groups.Count;
biggestGroupes = new();
foreach (var g in groups)
{
biggestGroupes.Add(g);
}
}
goto Start;
}
cptInWhileLoop++;
}
if (CanBeAdd == true)
{
groupe.users[chair] = MemoUser;
var personAlreadyUsed = PeopleAlreadyUsed.FirstOrDefault(x => x.Person == MemoUser);
personAlreadyUsed.AlreadyUsed = true;
}
}
}
groups.Add(groupe);
}
}
}
private static void GenerateCouples(List<Couple> couples)
{
for (int i = 0; i < 50; i++)
{
for (int j = 0; j < 50; j++)
{
if (i != j)
{
couples.Add(new Couple { x = i, y = j, Affected = false });
}
}
}
}
private static int GetUnusedPerson(List<PersonAlreadyUsed> personneDejUtilisees, int cptInWhileLoop)
{
var unusedPeople = personneDejUtilisees.Where(x=>x.AlreadyUsed==false).ToList();
if (unusedPeople.Count==0)
{
return -1;
}
// Retrieve a random element from the list using the random index
try
{
var randomPerson = unusedPeople[cptInWhileLoop];
return randomPerson.Person;
}
catch (Exception)
{
return -1;
}
}
private static void ResetAlreadyUsedPeople(List<PersonAlreadyUsed> personAlreadyUsed)
{
for (int i = 0; i < 50; i++)
{
personAlreadyUsed[i].AlreadyUsed = false;
}
}
private static List<PersonAlreadyUsed> CreateListPersonAlreadyUsed()
{
List < PersonAlreadyUsed > people = new();
for (int i = 0; i < 50; i++)
{
PersonAlreadyUsed dejUtilisee = new() { Person = i, AlreadyUsed = false };
people.Add(dejUtilisee);
}
return people;
}
private static bool CheckedIfCanBeAdd(int p, int v, List<Couple> couples)
{
bool ret = false;
if (p != v)
{
var comb1 = couples.FirstOrDefault(c => c.x == p && c.y == v);
var comb2 = couples.FirstOrDefault(c => c.x == v && c.y == p);
if (comb1.Affected == false && comb2.Affected == false)
{
ret = true;
comb1.Affected = true;
comb2.Affected = true;
}
}
return ret;
}
private static int GetRandomElement(List<PersonAlreadyUsed> personAlreadyUsed)
{
Random rand = new Random();
var peronStillAvailble = personAlreadyUsed.Where(x=>x.AlreadyUsed==false).ToList();
int randomIndex = rand.Next(peronStillAvailble.Count);
int randomElement = peronStillAvailble[randomIndex].Person;
return randomElement;
}
private static void AddCouple(Group groupe, List<Couple> couples)
{
foreach (var u1 in groupe.users)
{
foreach (var u2 in groupe.users)
{
if (u1 != u2)
{
var comb1 = couples.FirstOrDefault(c => c.x == u1 && c.y == u2);
var comb2 = couples.FirstOrDefault(c => c.x == u2 && c.y == u1);
comb1.Affected = true;
comb2.Affected = true;
}
}
}
}
}
public class PersonAlreadyUsed
{
public int Person { get; set; } =0;
public bool AlreadyUsed { get; set; }=false;
}
public class Couple
{
public int x { get; set; }
public int y { get; set; }
public bool Affected { get; set; }
}
public class Group
{
public int[] users { get; set; } = new int[5];
}
It seems that there is no solution.
Do you confirm?

How do you create buttons on a form through a method created in a class?

I'm trying to create a grid of buttons based on what number of rows and columns the user enters and my method that creates the grid isn't working. When I call it the grid doesn't get created.
The method is inside my TileClass and I'm trying to call it in my GameBoard form. I feel like I'm not using the class properly. I don't think I'm calling the method correctly because I'm thinking this should work.
This is what the form looks like
class TileClass : Button
{
public const int LEFT = 20;
public const int WIDTH = 50;
public const int HEIGHT = 50;
public const int TOP = 50;
public const int VGAP = 30;
public int x;
public int y;
public int column;
public int row;
private int incomingRow;
private int incomingColumn;
public int IncomingRow { get => incomingRow; set => incomingRow = value; }
public int IncomingColumn { get => incomingColumn; set => incomingColumn = value; }
public TileClass()
{
}
public void CreateGrid()
{
x = LEFT;
y = TOP;
column = IncomingColumn;
row = IncomingRow;
for (int i = 0; i < row; i++)
{
for (int j = 0; j < column; j++)
{
Button b = new Button();
b.Left = x;
b.Top = y;
b.Width = WIDTH;
b.Height = HEIGHT;
b.Text = j.ToString();
x += VGAP + HEIGHT;
this.Controls.Add(b);
}
}
}
}
Gameboard Form
public partial class GameBoard : Form
{
TileClass tileClass = new TileClass();
public GameBoard()
{
InitializeComponent();
}
private void txtEnter_Click(object sender, EventArgs e)
{
tileClass.IncomingColumn = int.Parse(txtColumn.Text);
tileClass.IncomingRow = int.Parse(txtRow.Text);
tileClass.CreateGrid();
}

There's a lot to do to make it happen:
class TileClass : Panel
{
...
public int IncomingRow {get; set;}
public int IncomingColumn { get; set; }
...
}
and remove:
private int incomingRow;
private int incomingColumn;
and the ideal approach would be using ResumeLayout before adding buttons and let the Gameboard form to be redrawn by calling Invalidate. What does invalidate method do?
note: try col=100, row=100 with and without ResumeLayout&Invalidate
public partial class GameBoard : Form
{
public GameBoard ()
{
InitializeComponent();
tileClass.Dock = DockStyle.Fill;
this.Controls.Add(tileClass);
}
TileClass tileClass = new TileClass();
private void txtEnter_Click(object sender, EventArgs e)
{
tileClass.IncomingColumn = int.Parse(txtColumn.Text);
tileClass.IncomingRow = int.Parse(txtRow.Text);
this.ResumeLayout(); //Important
tileClass.CreateGrid();
this.Invalidate(); // Important
}
}
and you can set more properties like, it needs more than this:
//tileClass.Location = new Point(10, 10); // not sure
tileClass.Dock = DockStyle.Fill;
//tileClass.Size = new Size(200, 200); // not sure
and instead of j < 5 you should use col and row:
for (int i = 0; i < row; i++)
{
for (int j = 0; j < column; j++)
{
Button b = new Button();
b.Left = x;
b.Top = y;
b.Width = WIDTH;
b.Height = HEIGHT;
b.Text = string.Format("({0},{1})" , i, j);
x += VGAP + HEIGHT;
this.Controls.Add(b);
}
x = LEFT; // not sure, plz calculate!
y += Top * (i+1); // not sure, plz calculate!
}

Calculating Aroon Indicator Series

I'm trying to build a class to create Aroon series. But it seems I don't understand the steps well. I'm not sure about for what purpose I have to use the period parameter.
Here is my first attempt:
/// <summary>
/// Aroon
/// </summary>
public class Aroon : IndicatorCalculatorBase
{
public override List<Ohlc> OhlcList { get; set; }
public int Period { get; set; }
public Aroon(int period)
{
this.Period = period;
}
/// <summary>
/// Aroon up: {((number of periods) - (number of periods since highest high)) / (number of periods)} x 100
/// Aroon down: {((number of periods) - (number of periods since lowest low)) / (number of periods)} x 100
/// </summary>
/// <see cref="http://www.investopedia.com/ask/answers/112814/what-aroon-indicator-formula-and-how-indicator-calculated.asp"/>
/// <returns></returns>
public override IIndicatorSerie Calculate()
{
AroonSerie aroonSerie = new AroonSerie();
int indexToProcess = 0;
while (indexToProcess < this.OhlcList.Count)
{
List<Ohlc> tempOhlc = this.OhlcList.Skip(indexToProcess).Take(Period).ToList();
indexToProcess += tempOhlc.Count;
for (int i = 0; i < tempOhlc.Count; i++)
{
int highestHighIndex = 0, lowestLowIndex = 0;
double highestHigh = tempOhlc.Min(x => x.High), lowestLow = tempOhlc.Max(x => x.Low);
for (int j = 0; j < i; j++)
{
if (tempOhlc[j].High > highestHigh)
{
highestHighIndex = j;
highestHigh = tempOhlc[j].High;
}
if (tempOhlc[j].Low < lowestLow)
{
lowestLowIndex = j;
lowestLow = tempOhlc[j].Low;
}
}
int up = ((this.Period - (i - highestHighIndex)) / this.Period) * 100;
aroonSerie.Up.Add(up);
int down = ((this.Period - (i - lowestLowIndex)) / this.Period) * 100;
aroonSerie.Down.Add(down);
}
}
return aroonSerie;
}
}
Is there anyone else tried to do that before?
Here is the csv file I use:
https://drive.google.com/file/d/0Bwv_-8Q17wGaRDVCa2FhMWlyRUk/view
But the result sets for Aroon up and down don't match with the results of aroon function in TTR package for R.
table <- read.csv("table.csv", header = TRUE, sep = ",")
trend <- aroon(table[,c("High", "Low")], n=5)
View(trend)
Screenshot of R result:
Thanks in advance,

#anilca,
for full Disclosure, I learned alot of things to answer your question(i knew nothing in the Finetec...). Thank you! it was an interesting experience!
There are several problems in your implementation:
In the statements:
i - highestHighIndex
and
i - lowestLowIndex
the variable "i" is less or equal to highestHighIndex, lowestLowIndex
so statements:
this.Period - (i - highestHighIndex)
and
this.Period - (i - lowestLowIndex)
will returns the wrong values (most of the time...)
Aroon up and down both of them are percentage, therefore "int" is a wrong data structure.
Because all variables in:
(this.Period - (i - highestHighIndex)) / this.Period)
and
((this.Period - (i - lowestLowIndex)) / this.Period)
are integers you won't recieve the right value.
one more thing the numbers in your excel are sorted from the newest to the oldest.(it effects on the R package)
I've implemented the algorithm based on your code(and your data order...)
public class Aroon : IndicatorCalculatorBase
{
public override List<OhlcSample> OhlcList { get; set; }
private readonly int _period;
public int Period
{
get { return _period; }
}
public Aroon(int period)
{
_period = period;
}
public override IIndicatorSerie Calculate()
{
var aroonSerie = new AroonSerie();
for (var i = _period; i < OhlcList.Count; i++)
{
var aroonUp = CalculateAroonUp(i);
var aroonDown = CalculateAroonDown(i);
aroonSerie.Down.Add(aroonDown);
aroonSerie.Up.Add(aroonUp);
}
return aroonSerie;
}
private double CalculateAroonUp(int i)
{
var maxIndex = FindMax(i - _period, i);
var up = CalcAroon(i - maxIndex);
return up;
}
private double CalculateAroonDown(int i)
{
var minIndex = FindMin(i - _period, i);
var down = CalcAroon(i - minIndex);
return down;
}
private double CalcAroon(int numOfDays)
{
var result = ((_period - numOfDays)) * ((double)100 / _period);
return result;
}
private int FindMin(int startIndex, int endIndex)
{
var min = double.MaxValue;
var index = startIndex;
for (var i = startIndex; i <= endIndex; i++)
{
if (min < OhlcList[i].Low)
continue;
min = OhlcList[i].Low;
index = i;
}
return index;
}
private int FindMax(int startIndex, int endIndex)
{
var max = double.MinValue;
var index = startIndex;
for (var i = startIndex; i <= endIndex; i++)
{
if (max > OhlcList[i].High)
continue;
max = OhlcList[i].High;
index = i;
}
return index;
}
}
public abstract class IndicatorCalculatorBase
{
public abstract List<OhlcSample> OhlcList { get; set; }
public abstract IIndicatorSerie Calculate();
}
public interface IIndicatorSerie
{
List<double> Up { get; }
List<double> Down { get; }
}
internal class AroonSerie : IIndicatorSerie
{
public List<double> Up { get; private set; }
public List<double> Down { get; private set; }
public AroonSerie()
{
Up = new List<double>();
Down = new List<double>();
}
}
public class OhlcSample
{
public double High { get; private set; }
public double Low { get; private set; }
public OhlcSample(double high, double low)
{
High = high;
Low = low;
}
}
Use this test method for debugging:
private Aroon _target;
[TestInitialize]
public void TestInit()
{
_target=new Aroon(5)
{
OhlcList = new List<OhlcSample>
{
new OhlcSample(166.90, 163.65),
new OhlcSample(165.00, 163.12),
new OhlcSample(165.91, 163.21),
new OhlcSample(167.29, 165.11),
new OhlcSample(169.99, 166.84),
new OhlcSample(170.92, 167.90),
new OhlcSample(168.47, 165.90),
new OhlcSample(167.75, 165.75),
new OhlcSample(166.14, 161.89),
new OhlcSample(164.77, 161.44),
new OhlcSample(163.19, 161.49),
new OhlcSample(162.50, 160.95),
new OhlcSample(163.25, 158.84),
new OhlcSample(159.20, 157.00),
new OhlcSample(159.33, 156.14),
new OhlcSample(160.00, 157.00),
new OhlcSample(159.35, 158.07),
new OhlcSample(160.70, 158.55),
new OhlcSample(160.90, 157.66),
new OhlcSample(164.38, 158.45),
new OhlcSample(167.75, 165.70),
new OhlcSample(168.93, 165.60),
new OhlcSample(165.73, 164.00),
new OhlcSample(167.00, 164.66),
new OhlcSample(169.35, 165.01),
new OhlcSample(168.12, 164.65),
new OhlcSample(168.89, 165.79),
new OhlcSample(168.65, 165.57),
new OhlcSample(170.85, 166.00),
new OhlcSample(171.61, 169.10)
}
};
}
[TestMethod]
public void JustToHelpYou()
{
var result = _target.Calculate();
var expectedUp = new List<double>()
{
100,80,60,40,20,0,0,0, 0,0,40,20,0,100,100,100,100,80, 60,100,80,60,40,100,100
};
var expectedDown = new List<double>
{
20,0,0,100,100,80,100,100,100,100,80,60,40,20,0,0,40,20,0,0,40,20,0,40,20
};
Assert.IsTrue( result.Up.SequenceEqual(expectedUp));
Assert.IsTrue( result.Down.SequenceEqual(expectedDown));
}

Just Add implementation of method HighestBarNum and LowestBarnum from your code
public class Aroon
{
public bool AroonDown
{
get;
set;
}
public double Period
{
get;
set;
}
public Aroon()
{
}
public IList<double> Execute(IList<double> src)
{
if (!this.AroonDown)
{
return this.ExecuteUp(src);
}
return this.ExecuteDown(src);
}
public IList<double> ExecuteDown(IList<double> src)
{
double[] period = new double[src.Count];
for (int i = 1; i < src.Count; i++)
{
double num = LowestBarNum(src, i, Period);
period[i] = 100 * (Period - num) / Period;
}
return period;
}
public IList<double> ExecuteUp(IList<double> src)
{
double[] period = new double[src.Count];
for (int i = 1; i < src.Count; i++)
{
double num = HighestBarNum(src, i, Period);
period[i] = 100 * ((Period - num) / Period;
}
return period;
}}

class AroonData
{
public double AroonUp;
public double AroonDown;
}
Calculation Class:
class AroonCalculationData
{
public double PeriodHigh;
public double PeriodLow;
public double SetAroonUp(List<MarketData> period, double lastHigh)
{
/*reverse the set so we can look at it from the current tick
on back, and ticksSinceHigh will set correctly*/
period.Reverse();
int ticksSinceHigh = 0;
double high = 0.0;//Set 0 so anything will be higher
for (int i = 0; i < period.Count; i++)
{
if (period[i].high > high)
{
high = period[i].high;
ticksSinceHigh = i;
}
}
/*This bit if for if the high just ticked out
of List<MarketData>.
Including the current tick (i = 0), List<MarketData> period
only looks back (period - 1) days.
This Checks to see if the last high is still in the set. if it's
not, and is still the high for the period, then ticksSinceHigh
is set to (period)*/
PeriodHigh = high;
if (PeriodHigh < lastHigh)
{
ticksSinceHigh = period.Count;
}
/*Aroon-Up Formula*/
return (double)(period.Count - ticksSinceHigh ) / (double)period.Count * 100.0;
}
//ASIDE FROM LOOKING FOR LOWS INSTEAD OF HIGHS, SAME AS AROON-UP
public double SetAroonDown(List<MarketData> period, double lastLow)
{
period.Reverse();
int daysSinceLow = 0;
double low = double.MaxValue;//Set max so anything will be lower
for (int i = 0; i < period.Count; i++)
{
if (period[i].low < low)
{
low = period[i].low;
daysSinceLow = i;
}
}
PeriodLow = low;
if (PeriodLow > lastLow)
{
daysSinceLow = period.Count;
}
return (double)(period.Count - daysSinceLow) / (double)period.Count * 100.0;
}
}
Calling code:
public AroonData[] Aroon(List<MarketData> marketData, int period)
{
AroonCalculationData[] calculationData = new AroonCalculationData[marketData.Count]
AroonData[] aroon= new AroonData[marketData.Count]
for (int i = period; i < marketData.Count; i++)
{
/*GetRange(i - period + 1, period) add 1 so that the current tick is
included in look back.
For example, if (period = 10) the first loop (i = 10) then (i -
period + 1) = 1 the set will be marketData 1 - 10.*/
/*calculationData[i - 1].PeriodHigh and calculationData[i - 1].PeriodLow
are for looking back at the last tick's look back period high and
low*/
data[i].AroonUp = calculationData[i].SetAroonUp(marketData.GetRange(i - period + 1, period), calculationData[i - 1].PeriodHigh);
data[i].AroonDown = calculationData[i].SetAroonDown(marketData.GetRange(i - period + 1, period), calculationData[i - 1].PeriodLow);
}
}
Side note:
One problem I had was comparing my data to TD Ameritrades Aroon, until i figured out their period is really period-1, so if you're comparing to TD keep that in mind.

Need help in data Binding in datagridview

I am new to c# and absolutely new to windows form application. I am Implementing a Sudoku
Solver I coded in C++ since i need a GUI. Using a DataGridView and need help with data binding without databases. Posting my code, please help. Need idea about
1. How to enable user enter data in datagridview and "inital" array.
2. How to read that data and copy in "copied" array.
3. How to Bind data to the DataGridView.
namespace WindowsFormsApplication3
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
bindGrid();
}
private void bindGrid()
{
List<TestCode> list = new List<TestCode>();
TestCode tt = new TestCode();
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
this.dataGridView1.DataSource = list;
}
public int i;
public int[,] initial;
public int[,] copied;
int inputvalue(int x, int y, int value)
{
initial = new int[9, 9];
copied = new int[9, 9];
for (int i = 0; i < 9; i++)
{
if (value == copied[x, i] || value == copied[i, y])
return 0;
}
for (i = (x / 3) * 3; i <= ((x / 3) * 3) + 2; i++)
for (int j = (y / 3) * 3; j <= ((y / 3) * 3) + 2; j++)
if (copied[i, j] == value)
return 0;
return value;
}
bool solve(int x, int y)
{
int i;
int temp;
if (copied[x, y] == 0)
{
for (i = 1; i < 10; i++)
{
temp = inputvalue(x, y, i);
if (temp > 0)
{
copied[x, y] = temp;
if (x == 8 && y == 8)
return true;
else if (x == 8)
{
if (solve(0, y + 1))
return true;
}
else
{
if (solve(x + 1, y))
return true;
}
}
}
if (i == 10)
{
if (copied[x, y] != initial[x, y])
copied[x, y] = 0;
return false;
}
}
if (x == 8 && y == 8)
return true;
else if (x == 8)
{
if (solve(0, y + 1))
return true;
}
else
{
if (solve(x + 1, y))
return true;
}
return true;
}
private void fillDatagrid()
{
}
private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
//this.dataGridView1.Rows.Add(new object[] { "Column1", "Column2", "Column3", "Column4","Column5","Column5","Column6","Column7","Column8","Column9", true });
//this.dataGridView1.DataSource = copied;
}
private void button1_Click(object sender, EventArgs e)
{
int i, j;
Form1 P = new Form1();
for (i = 0; i < 9; i++)
for (j = 0; j < 9; j++)
{
//dataGridView1[i, j];
// Console.SetCursorPosition(i + 1, j + 1);
//P.initial[i,j] = Console.ReadLine();
}
for (i = 0; i < 9; i++)
for (j = 0; j < 9; j++)
P.copied = P.initial;
if (P.solve(0, 0))
{
for (i = 0; i < 9; i++)
for (j = 0; j < 9; j++)
{
Console.SetCursorPosition(i + 1, j + 1);
Console.Write(" ", +P.copied[i, j]);
}
}
else
Console.Write(" NO Solution");
}
}
public class TestCode
{
public int Value1 { get; set; }
public int Value2 { get; set; }
public int Value3 { get; set; }
public int Value4 { get; set; }
public int Value5 { get; set; }
public int Value6 { get; set; }
public int Value7 { get; set; }
public int Value8 { get; set; }
public int Value9 { get; set; }
}
}

private void bindGrid()
{
List <TestCode> list = new List<TestCode>();
TestCode tt = new TestCode();
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
list.Add(tt);
this.dataGridView1.DataSource = list;
this.dataGridView1.DataBind();
}

Save control state when form is closed

Hi I am trying to save the color state of this 4x4 grid of buttons created dynamically using a 2D array into an xml document:
However when I press save I keep getting this message:
I can make this work if I use a one dimensional array for the buttons but that will not give me the grid that I want but when I use a 2D array for the buttons it wont work:
What can I change so I can get this to work any suggestion are much appreciated:
This is my code that I have:
FormState class:
public class FormState
{
public string ButtonBackColor { get; set; }
}
Form code:
public partial class Form1 : Form
{
int col = 4;
int row = 4;
Button[,] buttons;
FormState[,] states;
public Form1()
{
InitializeComponent();
buttons = new Button[col, row];
states = new FormState[col, row];
}
public void placeRows()
{
for (int r = 0; r < row; r++)
{
createColumns(r);
}
}
public void createColumns(int r)
{
int s = r * 25; //gap
for (int c = 0; c < col; c++)
{
buttons[r, c] = new Button();
buttons[r, c].SetBounds(75 * c, s, 75, 25);
buttons[r, c].Text = Convert.ToString(c);
buttons[r, c].Click += new EventHandler(grid_Click);
panel1.Controls.Add(buttons[r, c]);
}
}
int count = 0;
//backcolor change
void grid_Click(object sender, EventArgs e)
{
Button button = sender as Button;
if (count == 0)
{
button.BackColor = Color.Red;
count++;
}
else if (count == 1)
{
button.BackColor = Color.Blue;
count--;
}
}
private void Form1_Load(object sender, EventArgs e)
{
placeRows();
if (File.Exists("config.xml"))
{
loadConfig();
}
for (int i = 0; i < col; ++i)
{
for (int j = 0; j < row; ++j)
{
if (states[i,j] != null)
{
buttons[i,j].BackColor = ColorTranslator.FromHtml(states[i,j].ButtonBackColor);
}
}
}
}
//method to load file
private void loadConfig()
{
XmlSerializer ser = new XmlSerializer(typeof(FormState[]));
using (FileStream fs = File.OpenRead("config.xml"))
{
states = (FormState[,])ser.Deserialize(fs);
}
}
private void writeConfig()
{
for (int i = 0; i < col; i++)
{
for (int j = 0; j < row; j++)
{
if (states[i,j] == null)
{
states[i,j] = new FormState();
}
states[i,j].ButtonBackColor = ColorTranslator.ToHtml(buttons[i,j].BackColor);
}
using (StreamWriter sw = new StreamWriter("config.xml"))
{
XmlSerializer ser = new XmlSerializer(typeof(FormState[]));
ser.Serialize(sw, states);
}
}
}
private void btnSave_Click(object sender, EventArgs e)
{
writeConfig();
}
}

This may not be an ideal solution (and I haven't tried it, so it may not even work), but you could create a nested array instead of a 2-D array. Something like
FormStates[][] states = new FormStates[row][];
for(Int32 i = 0; i < row; i++)
{
states[i] = new FormStates[col];
}
Instead of indexing using states[i, j], you would use states[i][j]. Since 1-D arrays are serializable, this might work.
Edit
Slightly longer example, based on your code:
public partial class Form1 : Form
{
int col = 4;
int row = 4;
Button[][] buttons;
FormState[][] states;
public Form1()
{
InitializeComponent();
buttons = new Button[col][];
states = new FormState[col][];
for(Int32 c = 0; c < col; c++)
{
buttons[c] = new Button[row];
states[c] = new FormState[row];
}
}
public void createColumns(int r)
{
int s = r * 25; //gap
for (int c = 0; c < col; c++)
{
buttons[r][c] = new Button();
buttons[r][c].SetBounds(75 * c, s, 75, 25);
buttons[r][c].Text = Convert.ToString(c);
buttons[r][c].Click += new EventHandler(grid_Click);
panel1.Controls.Add(buttons[r][c]);
}
}
}
This should be enough to give you the syntax to change the rest of your code.
You will also want to change your XmlSerializer declarations to use typeof(FormState[][]) instead of just typeof(FormState[]).

Admittedly I haven't put much thought into this but as per comments you cant serialize multi dimensional arrays so you might:
[Serializable]
public class FormState
{
public int RowIndex { get; set; }
public int ColIndex { get; set; }
public string BackColor { get; set; }
}
[Serializable]
public class Layout : Collection<FormState> {
public Layout(){}
}
..
public void SomeCallingMethod() {
Layout l = new Layout();
foreach (FormState fs in l) {
buttons[fs.RowIndex, fs.ColIndex].BackColor = ColorTranslator.FromHtml(fs.BackColor);
}
}
Or use a List if necessary and serialize that.