Python打印Unicode字符

Question

我正在制作纸牌游戏,但我遇到了似乎是一个编码问题.我正在尝试打印这样一张卡片:

def print(self):
    print("|-------|")
    print("| %s     |" % self.value)
    print("|       |")
    print("|   %s   |" % self.suit.encode("utf-8"))
    print("|       |")
    print("|    %s  |" % self.value)
    print("|-------|")

这就是我要的:

|-------|
| 10    |
|       |
|   ?   |
|       |
|    10 |
|-------|

......但这就是我得到的:

|-------|
| 10    |
|       |
|   b'\xe2\x99\xa6'   |
|       |
|    10 |
|-------|

如果重要的话,我在Windows和Python 3上.

self.suit的值可以是以下任何一个:

spade = "?"
heart = "?"
diamond = "?"
club = "?"

如果我删除.encode("utf-8"),我会收到此错误:

Traceback(最近一次调用最后一次):

  File "main.py", line 79, in <module>
    start()
  File "main.py", line 52, in start
    play()
  File "main.py", line 64, in play
    card.print()
  File "main.py", line 36, in print
    print("|   \u2660   |")
  File "C:\Python34\lib\encodings\cp850.py", line 19, in encode
    return codecs.charmap_encode(input,self.errors,encoding_map)[0]
UnicodeEncodeError: 'charmap' codec can't encode character '\u2660' in position
4: character maps to <undefined>

Answer 1

这利用了Windows控制台中的OEM代码页为控制字符打印一些可见字符的事实.该卡西服cp437和cp850是chr(3)-chr(6).Python 3(3.6之前的版本)不会为黑色菱形打印Unicode字符,但它是你为U + 0004获得的:

>>> print('\N{BLACK DIAMOND SUIT}')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python33\lib\encodings\cp437.py", line 19, in encode
    return codecs.charmap_encode(input,self.errors,encoding_map)[0]
UnicodeEncodeError: 'charmap' codec can't encode character '\u2666' in position 0: character maps to <undefined>
>>> print(chr(4))
?

因此:

#!python3
#coding: utf8
class Card:
    def __init__(self,value,suit):
        self.value = value
        self.suit = suit    # 1,2,3,4 = ????

    def print(self):
        print("?????????")
        print("| {:<2}    |".format(self.value))
        print("|       |")
        print("|   {}   |".format(chr(self.suit+2)))
        print("|       |")
        print("|    {:>2} |".format(self.value))
        print("?????????") 

输出:

>>> x=Card('K',4)
>>> x.print()
?????????
| K     |
|       |
|   ?   |
|       |
|     K |
?????????
>>> x=Card(10,3)
>>> x.print()
?????????
| 10    |
|       |
|   ?   |
|       |
|    10 |
?????????

Python 3.6更新

Python 3.6使用Windows Unicode API进行打印,因此现在不需要控制字符技巧,可以使用新的格式字符串:

#!python3.6
#coding: utf8
class Card:
    def __init__(self,value,suit):
        self.value = value
        self.suit = '????'[suit-1] # 1,2,3,4 = ????

    def print(self):
        print('?????????')
        print(f'| {self.value:<2}    |')
        print('|       |')
        print(f'|   {self.suit}   |')
        print('|       |')
        print(f'|    {self.value:>2} |')
        print('?????????') 

输出:

>>> x=Card('10',3)
>>> x.print()
?????????
| 10    |
|       |
|   ?   |
|       |
|    10 |
?????????