public void SetValue(int x, int y, int value, Digit.Kind kind)
{
// Save the current digits in case something goes wrong
var savedDigits = DuplicateDigits();
try
{
try
{
// Attempt to set the specified value
_digits[x, y].SetValue(value, kind);
}
catch (InvalidDigitException)
{
// Digit was invalid, so board would have become invalid
throw new InvalidBoardException(x, y);
}
// Exclude the value from the rest of the row and column
for (var i = 0; i < Size; i++)
{
if (i != x)
{
Exclude(i, y, value);
}
if (i != y)
{
Exclude(x, i, value);
}
}
// Exclude the value from the rest of the block
for (var j = (y / 3) * 3; j < ((y / 3) * 3) + 3; j++)
{
for (var i = (x / 3) * 3; i < ((x / 3) * 3) + 3; i++)
{
if ((i != x) || (j != y))
{
Exclude(i, j, value);
}
}
}
}
catch (InvalidBoardException)
{
// Recover from invalid board and re-throw
_digits = savedDigits;
throw;
}
}
public bool ChangeSelectedValue(int value, Digit.Kind kind)
{
var changed = false;
// Get the current position
_conflictPosition = null;
var x = (int)_markerPosition.X;
var y = (int)_markerPosition.Y;
if (Digit.Unknown == value)
{
// Clear the digit's value if set
if (_board.GetDigit(x, y).ValueKnown)
{
_board.ClearValue(x, y);
changed = true;
}
}
else
{
try
{
// Set the cell's value
_board.SetValue(x, y, value, kind);
changed = true;
}
catch (InvalidBoardException e)
{
// Would have created an invalid board; identify the location of the conflict
_conflictPosition = new Point(e.X, e.Y);
}
}
// Update the display
UpdateDisplay(_board);
return(changed);
}
