Gera.Chess 1.0.2

Gera Chess Library

Chess logic made with C# and ♥ by Geras1mleo

Chess lib includes:

• Chess board with 2-dimentional array of Pieces
• Generation, Validation and Execution of Moves on Chess board
• Logic to Convert:
  • Move into SAN and back into Move object
  • Chess Boardinto FEN and back into ChessBoard object
  • Chess Game into PGN and back into ChessBoard object
• Event Handlers:
  • OnInvalidMoveKingChecked - Raises when trying to execute move that places own king in check
  • OnWhiteKingCheckedChanged/OnBlackKingCheckedChanged with state (checked or not) and its position
  • OnPromotePawn with PromotionEventArgs.PromotionResult (default: PromotionToQueen)
  • OnEndGame with according end game info (Win/Loss/Draw)
  • OnCaptured with captured piece and all recently captured pieces (White/Black)
• End Game Declaration: Draw or Resign of one of sides
• Navigation between executed moves:
  • First/Last
  • Next/Previous
  • Also: board.MoveIndex property to navigate direct to specific move
• Cancelation of last executed move

Usage!

Example simple console chess game:

using Chess;

var board = new ChessBoard();

while (!board.IsEndGame)
{
    Console.WriteLine(board.ToAscii());
    board.Move(Console.ReadLine());
}

Console.WriteLine(board.ToAscii());
Console.WriteLine(board.ToPgn());

// Outcome after last move:
// Qh5
//   ┌────────────────────────┐
// 8 │ r  n  b  q  k  b  n  r │
// 7 │ p  p  p  p  p  .  .  p │
// 6 │ .  .  .  .  .  .  .  . │
// 5 │ .  .  .  .  .  p  p  Q │
// 4 │ .  .  .  .  P  P  .  . │
// 3 │ .  .  .  .  .  .  .  . │
// 2 │ P  P  P  P  .  .  P  P │
// 1 │ R  N  B  .  K  B  N  R │
//   └────────────────────────┘
//     a  b  c  d  e  f  g  h  
//
// 1. e4 f5 2. f4 g5 3. Qh5# 1-0

Example random chess game:

while (!board.IsEndGame)
{
    var moves = board.Moves();
    board.Move(moves[Random.Shared.Next(moves.Length)]);
}

Console.WriteLine(board.ToAscii());
Console.WriteLine(board.ToPgn());

// Todo: End game Insufficient Material

Track Pieces

Track pieces on position using indexers:

board["c2"]... 		  	// => White Pawn
board['g', 8]... 		// => Black Bishop

// Counting from 0
board[0, 0]...			// => White Rook
board[new Position(4, 7)]... 	// => Black King

Track captured pieces:

board.CapturedWhite... // => White pieces that has been captured by black player
board.CapturedBlack... // => Black pieces that has been captured by white player
// Properties above work just fine when board has been loaded from FEN

Track kings and their state (Checked/Unchecked):

board.WhiteKing... // => White king position on chess board (Calculated property)
board.BlackKing... // => Black king position on chess board (Calculated property)

board.WhiteKingChecked... // => State of White king (Referred property)
board.BlackKingChecked... // => State of Black king (Referred property)

Move Pieces

Move pieces using SAN/LAN:

board.Move("e4");	// => Good
board.Move("N-f6");	// => Good
board.Move("NXf6");	// => Good
board.Move("dxc3 e.p.");// => Good
board.Move("Pe4");	// => Good 
board.Move("Pe5xd6");	// => Good
board.Move("O-O-O+");	// => Good

board.Move("ne5");	// => Bad
board.Move("e8=K");	// => Bad
board.Move("0-0");	// => Bad

Move pieces using Move object and corresponding positions:

board.Move(new Move("b1", "c3"));

Ambiguity:

board.LoadPgn("1. e4 e5 2. Ne2 f6");
board.ToAscii();
//   ┌────────────────────────┐
// 8 │ r  n  b  q  k  b  n  r │
// 7 │ p  p  p  p  .  .  p  p │
// 6 │ .  .  .  .  .  p  .  . │
// 5 │ .  .  .  .  p  .  .  . │
// 4 │ .  .  .  .  P  .  .  . │
// 3 │ .  .  .  .  .  .  .  . │
// 2 │ P  P  P  P  N  P  P  P │
// 1 │ R  N  B  Q  K  B  .  R │
//   └────────────────────────┘
//     a  b  c  d  e  f  g  h  

board.Move("Nc3"); 	// => Throws exception: ChessSanTooAmbiguousException. Both knights can move to c3
board.Move("Nc4"); 	// => Throws exception: ChessSanNotFoundException. None of knights can move to c3

Load Chess game/board

Load chess board Variant: From Position (FEN):

board.LoadFen("1nbqkb1r/pppp1ppp/2N5/4p3/3P4/8/PPP1PPPP/RN2KB1R w KQk - 0 1");
board.ToAscii();
//   ┌────────────────────────┐
// 8 │ .  n  b  q  k  b  .  r │
// 7 │ p  p  p  p  .  p  p  p │
// 6 │ .  .  N  .  .  .  .  . │
// 5 │ .  .  .  .  p  .  .  . │
// 4 │ .  .  .  P  .  .  .  . │
// 3 │ .  .  .  .  .  .  .  . │
// 2 │ P  P  P  .  P  P  P  P │
// 1 │ R  N  .  .  K  B  .  R │
//   └────────────────────────┘
//     a  b  c  d  e  f  g  h  

board.CapturedWhite... // => { White Bishop, White Queen }
board.CapturedBlack... // => { Black Rook, Black Knight }

// Stalemate
board.LoadFen("rnb1kbnr/pppppppp/8/8/8/8/5q2/7K w kq - 0 1");
board.EndGame... // => { EndgameType = Stalemate, WonSide = null }

Load full chess game from PGN:

board.LoadPgn(
@"[Variant ""From Position""]
[FEN ""rnbqkbnr/ppp1pppp/8/3p4/4P3/8/PPPP1PPP/RNBQKBNR w KQkq - 0 1""]
            
1.exd5 e6 2.dxe6 fxe6 3.d4(3.f4 g5 4.fxg5) 3... c5 4.b4");

board.ToAscii();
//   ┌────────────────────────┐
// 8 │ r  n  b  q  k  b  n  r │
// 7 │ p  p  .  .  .  .  p  p │
// 6 │ .  .  .  .  p  .  .  . │
// 5 │ .  .  p  .  .  .  .  . │
// 4 │ .  P  .  P  .  .  .  . │
// 3 │ .  .  .  .  .  .  .  . │
// 2 │ P  .  P  .  .  P  P  P │
// 1 │ R  N  B  Q  K  B  N  R │
//   └────────────────────────┘
//     a  b  c  d  e  f  g  h  

Alternative moves and comments are getting (temporary) skipped In further versions: Navigate between alternative branches Saving and adding of comments to each move

End Game

Declare Draw/Resign:

board.Draw();
board.EndGame... // => { EndgameType = DrawDeclared, WonSide = null }

board.Clear();

board.Resign(PieceColor.Black);
board.EndGame... // => { EndgameType = Resigned, WonSide = White }

Found a bug?

Drop to Issues Or to: sviatoslav.harasymchuk@gmail.com Thanks in advance!