I think your code is equivalent to this:
if( ( arrayX == 0 || arrayX == 7 ) && board.GetBoard(arrayX + 1, arrayY - 1).Piece == null)
return true;
I think your code is equivalent to this:
if( ( arrayX == 0 || arrayX == 7 ) && board.GetBoard(arrayX + 1, arrayY - 1).Piece == null)
return true;