有关python中字符的unicode表信息

Question

python中是否有一种方法可以获取给定字符的技术信息，例如在Unicode表中显示的那样？（请参阅https://unicode-table.com/en/）

示例：对于字母“？”

• 名称>带有双坟墓的拉丁大写字母E
• Unicode编号> U + 0204
• HTML代码>Ȅ
• 团体>拉丁扩展B
• 小写字母>？

我真正需要的是获取任何Unicode数字（例如U + 0204）对应的名称（带Double Grave的拉丁大写字母E）和小写版本（此处为“？”）。

大致来说：
输入= Unicode数字
输出=对应信息

我能够找到的最接近的东西是fontTools库，但是我似乎找不到任何有关如何使用它的教程/文档。

谢谢。

Answer 1

标准模块unicodedata定义了很多属性，但不是全部。快速浏览一下其来源就可以证实这一点。

幸运的是unicodedata.txt，它的来源数据文件并不难解析。每行仅由15个元素组成，;彼此分隔，因此非常适合解析。使用ftp://ftp.unicode.org/Public/3.0-Update/UnicodeData-3.0.0.html上元素的描述，可以创建一些类来封装数据。我从该列表中选取了类元素的名称。同一页面上解释了每个元素的含义。

确保首先下载ftp://ftp.unicode.org/Public/UNIDATA/UnicodeData.txt和ftp://ftp.unicode.org/Public/UNIDATA/Blocks.txt，并将它们放在与此相同的文件夹中程序。

代码（已通过Python 2.7和3.6测试）：

# -*- coding: utf-8 -*-

class UnicodeCharacter:
    def __init__(self):
        self.code = 0
        self.name = 'unnamed'
        self.category = ''
        self.combining = ''
        self.bidirectional = ''
        self.decomposition = ''
        self.asDecimal = None
        self.asDigit = None
        self.asNumeric = None
        self.mirrored = False
        self.uc1Name = None
        self.comment = ''
        self.uppercase = None
        self.lowercase = None
        self.titlecase = None
        self.block = None

    def __getitem__(self, item):
        return getattr(self, item)

    def __repr__(self):
        return '{'+self.name+'}'

class UnicodeBlock:
    def __init__(self):
        self.first = 0
        self.last = 0
        self.name = 'unnamed'

    def __repr__(self):
        return '{'+self.name+'}'

class BlockList:
    def __init__(self):
        self.blocklist = []
        with open('Blocks.txt','r') as uc_f:
            for line in uc_f:
                line = line.strip(' \r\n')
                if '#' in line:
                    line = line.split('#')[0].strip()
                if line != '':
                    rawdata = line.split(';')
                    block = UnicodeBlock()
                    block.name = rawdata[1].strip()
                    rawdata = rawdata[0].split('..')
                    block.first = int(rawdata[0],16)
                    block.last = int(rawdata[1],16)
                    self.blocklist.append(block)
            # make 100% sure it's sorted, for quicker look-up later
            # (it is usually sorted in the file, but better make sure)
            self.blocklist.sort (key=lambda x: block.first)

    def lookup(self,code):
        for item in self.blocklist:
            if code >= item.first and code <= item.last:
                return item.name
        return None

class UnicodeList:
    """UnicodeList loads Unicode data from the external files
    'UnicodeData.txt' and 'Blocks.txt', both available at unicode.org

    These files must appear in the same directory as this program.

    UnicodeList is a new interpretation of the standard library
    'unicodedata'; you may first want to check if its functionality
    suffices.

    As UnicodeList loads its data from an external file, it does not depend
    on the local build from Python (in which the Unicode data gets frozen
    to the then 'current' version).

    Initialize with

        uclist = UnicodeList()
    """
    def __init__(self):

        # we need this first
        blocklist = BlockList()
        bpos = 0

        self.codelist = []
        with open('UnicodeData.txt','r') as uc_f:
            for line in uc_f:
                line = line.strip(' \r\n')
                if '#' in line:
                    line = line.split('#')[0].strip()
                if line != '':
                    rawdata = line.strip().split(';')
                    parsed = UnicodeCharacter()
                    parsed.code = int(rawdata[0],16)
                    parsed.characterName = rawdata[1]
                    parsed.category = rawdata[2]
                    parsed.combining = rawdata[3]
                    parsed.bidirectional = rawdata[4]
                    parsed.decomposition = rawdata[5]
                    parsed.asDecimal = int(rawdata[6]) if rawdata[6] else None
                    parsed.asDigit = int(rawdata[7]) if rawdata[7] else None
                    # the following value may contain a slash:
                    #  ONE QUARTER ... 1/4
                    # let's make it Python 2.7 compatible :)
                    if '/' in rawdata[8]:
                        rawdata[8] = rawdata[8].replace('/','./')
                        parsed.asNumeric = eval(rawdata[8])
                    else:
                        parsed.asNumeric = int(rawdata[8]) if rawdata[8] else None
                    parsed.mirrored = rawdata[9] == 'Y'
                    parsed.uc1Name = rawdata[10]
                    parsed.comment = rawdata[11]
                    parsed.uppercase = int(rawdata[12],16) if rawdata[12] else None
                    parsed.lowercase = int(rawdata[13],16) if rawdata[13] else None
                    parsed.titlecase = int(rawdata[14],16) if rawdata[14] else None
                    while bpos < len(blocklist.blocklist) and parsed.code > blocklist.blocklist[bpos].last:
                        bpos += 1
                    parsed.block = blocklist.blocklist[bpos].name if bpos < len(blocklist.blocklist) and parsed.code >= blocklist.blocklist[bpos].first else None
                    self.codelist.append(parsed)

    def find_code(self,codepoint):
        """Find the Unicode information for a codepoint (as int).

        Returns:
            a UnicodeCharacter class object or None.
        """
        # the list is unlikely to contain duplicates but I have seen Unicode.org
        # doing that in similar situations. Again, better make sure.
        val = [x for x in self.codelist if codepoint == x.code]
        return val[0] if val else None

    def find_char(self,str):
        """Find the Unicode information for a codepoint (as character).

        Returns:
            for a single character: a UnicodeCharacter class object or
            None.
            for a multicharacter string: a list of the above, one element
            per character.
        """
        if len(str) > 1:
            result = [self.find_code(ord(x)) for x in str]
            return result
        else:
            return self.find_code(ord(str))

加载后，您现在可以使用

>>> ul = UnicodeList()     # ONLY NEEDED ONCE!
>>> print (ul.find_code(0x204))
{LATIN CAPITAL LETTER E WITH DOUBLE GRAVE}

默认情况下显示为字符名称（Unicode将其称为“代码点”），但是您也可以检索其他属性：

>>> print ('%04X' % uc.find_code(0x204).lowercase)
0205
>>> print (ul.lookup(0x204).block)
Latin Extended-B

并且（只要您没有获得None）甚至将它们链接起来：

>>> print (ul.find_code(ul.find_code(0x204).lowercase))
{LATIN SMALL LETTER E WITH DOUBLE GRAVE}

它不依赖于您的特定Python版本；您可以随时从unicode.org下载更新列表，并确保获得最新信息：

import unicodedata
>>> print (unicodedata.name('\U0001F903'))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: no such name
>>> print (uclist.find_code(0x1f903))
{LEFT HALF CIRCLE WITH FOUR DOTS}

（经Python 3.5.3。测试）。

当前定义了两个查找功能：

• find_code(int)通过代码点将字符信息查找为整数。
• find_char(string)在中查找字符的字符信息string。如果只有一个字符，则返回一个UnicodeCharacter对象；否则，返回一个对象。如果还有更多，它将返回对象列表。

之后import unicodelist（假设您将其另存为unicodelist.py），则可以使用

>>> ul = UnicodeList()
>>> hex(ul.find_char(u'è').code)
'0xe8'

查找任何字符的十六进制代码，以及列表理解，例如

>>> l = [hex(ul.find_char(x).code) for x in 'Hello']
>>> l
['0x48', '0x65', '0x6c', '0x6c', '0x6f']

对于更长的字符串。请注意，如果您想要的只是一个字符串的十六进制表示，那么实际上并不需要所有这些！这足以：

 l = [hex(ord(x)) for x in 'Hello']

该模块的目的是使您可以轻松访问其他 Unicode属性。一个更长的例子：

str = 'Héllo...'
dest = ''
for i in str:
    dest += chr(ul.find_char(i).uppercase) if ul.find_char(i).uppercase is not None else i
print (dest)

HÉLLO...

并根据您的示例显示字符的属性列表：

letter = u'?'
print ('Name > '+ul.find_char(letter).name)
print ('Unicode number > U+%04x' % ul.find_char(letter).code)
print ('Bloc > '+ul.find_char(letter).block)
print ('Lowercase > %s' % chr(ul.find_char(letter).lowercase))

（我省略了HTML；这些名称未在Unicode标准中定义。）