在控制台上格式化输出-Python

Question

First question here, so apologize for the messy formatting.

I was hoping was a couple of pointers. I'm trying to implement a board game as an exercise for OOP. So I need a 8x8 'board', similar to a chess board, but the game play, ie putting pieces on the board only occurs on 7x7 cells. I've implemented it by iterating over a list of 8 lists. Here's the code:

class Board(object):

    def __init__(self):
        self.Board = [[[] for x in range(LENGTH)] for y in range(LENGTH)]

    def makeBoard(self, initial_blocked):

        for row in range(LENGTH):
            for col in range(LENGTH):
                self.Board[row][col] = 'e'
        self.Board[0][1] = 'A'
        self.Board[0][2] = 'B'
        self.Board[0][3] = 'C'
        self.Board[0][4] = 'D'
        self.Board[0][5] = 'E'
        self.Board[0][6] = 'F'
        self.Board[0][7] = 'G'

        self.Board[0][0] = '~'
        self.Board[1][0] = '1'
        self.Board[2][0] = '2'
        self.Board[3][0] = '3'
        self.Board[4][0] = '4'
        self.Board[5][0] = '5'
        self.Board[6][0] = '6'
        self.Board[7][0] = '7'

        if True:
            while initial_blocked > 0:
                position_x = rand(0, 7)
                position_y = rand(0, 7)
                if self.Board[position_x][position_y] == 'e':
                    self.Board[position_x][position_y] = 'X'
                    initial_blocked -= 1

        for line in range(8):
            print(self.Board[line])

The output looks like this:

['~', 'A', 'B', 'C', 'D', 'E', 'F', 'G']
['1', 'e', 'e', 'e', 'e', 'e', 'e', 'e']
['2', 'e', 'e', 'e', 'X', 'X', 'e', 'e']
['3', 'e', 'X', 'e', 'e', 'X', 'e', 'e']
['4', 'e', 'e', 'e', 'X', 'e', 'e', 'e']
['5', 'e', 'e', 'e', 'e', 'e', 'e', 'e']
['6', 'e', 'e', 'e', 'e', 'e', 'e', 'e']
['7', 'e', 'e', 'e', 'e', 'e', 'e', 'e']

1st row and column will be used for the user input( eg A1, D4) 'X' are cells that are blocked and 'e' stands for empty. The players enter where they want to keep their piece, eg A1, and the 'e' will be changed to 'b' or 'w', black or white. Haven't still figured out how I'll do that, but first things first.
I want it to resemble -at least somewhat- a board. If I try to print out a board using many print()s, I cant figure out how I can change a cell on that board, that references the the same cell as the index. ie input A1 changes the list at [1][1] and that cell on the board.

I hope this makes sense. Thanks!

Answer 1

I've made a few optimizations to your code that you may find helpful. Rather than doing all of those separate statements to initialise the column and row headers, we can do that using loops. Also, it's good to iterate over lists directly, rather than using indices, when practical. And I've changed some of your names to make them comply with the PEP-0008 style guide; that makes it easier for others to read your code, especially if they're using colour-coded syntax highlighting.

from random import seed, randrange

seed(123)

LENGTH = 8

# A dict for converting reference letters to integers
letters = {ch: i for i, ch in enumerate('ABCDEFG', 1)}

def ref_to_index(ref):
    ''' Convert a ref from A1 form to a tuple of (row, col) integers
        Return None if the ref is invalid 
    '''
    if len(ref) != 2:
        return None
    x, y = ref.upper()
    if x not in letters or y not in '1234567':
        return None
    return int(y), letters[x]

class Board(object):
    def __init__(self):
        # Initialize the board lists
        self.board = [['e'] * LENGTH for y in range(LENGTH)]
        # Add the column headers
        self.board[0][:] = list('~ABCDEFG')
        # Add the row headers
        for i, row in enumerate(self.board[1:], 1):
            row[0] = str(i)

    def add_blocks(self, initial_blocked):
        for _ in range(initial_blocked):
            while True:
                position_x = randrange(1, LENGTH)
                position_y = randrange(1, LENGTH)
                row = self.board[position_y]
                if row[position_x] == 'e':
                    row[position_x] = 'X'
                    break

    def reset(self):
        ''' Make all the board cells empty '''
        size = LENGTH - 1
        for row in self.board[1:]:
            row[1:] = ['e'] * size

    def show(self):
        for row in self.board:
            print(' '.join(row))
        print()

# test

board = Board()
board.show()
board.add_blocks(7)
board.show()
while True:
    ref = input('Select a move: ')
    idx = ref_to_index(ref)
    if idx is None:
        print('Invalid move')
        continue
    y, x = idx
    row = board.board[y]
    if row[x] != 'e':
        print("That cell isn't empty")
        continue
    row[x] = 'b'
    board.show()