用python中的字典值替换正则表达式匹配组答案

【问题标题】：replace a regex match group with a dictionary value in python用python中的字典值替换正则表达式匹配组
【发布时间】：2014-09-02 05:09:40
【问题描述】：

我正在从事一个爱好项目，以编写流行的 Amiga BBS 软件程序的克隆。该程序中的一个功能是使用短代码功能，就像论坛上的 BBCodes 一样，可以更改文本颜色并进行一些屏幕格式化。我无法弄清楚如何替换从文本文件中读取的 RegEx 匹配组。带有字典中的值。例如，我们有一个包含短代码的文本文件：

{c2}************************************************************
**                                                        **
**  {R3}{c7}This is the SYS.INFO file. This file will show the{c2}    **
**  {c7}caller, information that you want to share, about{c2}     **
**  {c7}your BBS.{c2}                                             **
**                                                        **
************************************************************

字典如下所示：

ansi_colors = {"c0" : "\033[0.30m" , "c1" : "\033[31m" , "c2" : "\033[0.32m" , "c3" : "\033[0.33m" , "c4" : "\033[0.34m" , "c5" : "\033[0.35m" , "c6" : "\033[0.36m" , "c7" : "\033[0.37m" , "c8" : "\033[1m\033[30m" , "ca" : "\033[1m\033[31m" , "cb" : "\033[1m\033[32m" , "cc" : "\033[1m\033[33m" , "cd" : "\033[1m\033[34m" , "ce" : "\033[1m\033[35m" , "cf" : "\033[1m\033[36m" , "cg" : "\033[1m\033[37m" , "R1" : "\033[41m" , "R2" : "\033[42m" , "R3" : "\033[43m" , "R4" : "\033[44m" , "R5" : "\033[45m" , "R6" : "\033[46m" , "R7" : "\033[47m"}

因此，例如，当程序遇到 {c8} 时，它会以字典相应键中的值指定的适当颜色打印其后的文本。因此，当您遇到 {R3}{c7} 时，应用程序应将 {R3} 替换为正确的 ANSI 反转文本，然后 {c7} 将文本的颜色更改为适当的颜色。所以在这种情况下，青色背景上的白色文本。

我遇到的麻烦是，将与键对应的正则表达式匹配组替换为字典中的正确值。这是我的代码：

#!/usr/bin/env python

import sys
import re

ansiColors = {"c0" : "\033[0.30m" , "c1" : "\033[31m" , "c2" : "\033[0.32m" , "c3" : "\033[0.33m" , "c4" : "\033[0.34m" , "c5" : "\033[0.35m" , "c6" : "\033[0.36m" , "c7" : "\033[0.37m" , "c8" : "\033[1m\033[30m" , "ca" : "\033[1m\033[31m" , "cb" : "\033[1m\033[32m" , "cc" : "\033[1m\033[33m" , "cd" : "\033[1m\033[34m" , "ce" : "\033[1m\033[35m" , "cf" : "\033[1m\033[36m" , "cg" : "\033[1m\033[37m" , "R1" : "\033[41m" , "R2" : "\033[42m" , "R3" : "\033[43m" , "R4" : "\033[44m" , "R5" : "\033[45m" , "R6" : "\033[46m" , "R7" : "\033[47m"}

display = open('sys.infox','r')
for lines in display:
    lines = re.sub(r'(\{)(\w+)(\})', ansiColors[lines.group(2)] , lines)
    print lines.strip('\n')

这段代码总是给我错误：

Traceback（最近一次调用最后一次）：文件“/private/var/folders/k9/z1vjbjwn6c31xts7l07b2m080000gn/T/Cleanup At Startup/newtestmci-431326805.359.py”，第 10 行，在行 = re.sub(r'({)(\w+)(})', ansiColors[lines.group(2)] , 行) AttributeError: 'str' 对象没有属性 'group'

我迷路了，我无法绕开它。有人有什么建议吗？告诉我我错在哪里。对python还是很陌生，所以对我来说放轻松。

【问题讨论】：

标签： python regex replace

【解决方案1】：

lines 只是一个字符串；您正在尝试将其用作匹配对象。

您可以使用替换回调来实现此目的：

def repl(m):
    return ansiColors[m.group(2)]

display = open('sys.infox','r')
for lines in display:
    lines = re.sub(r'(\{)(\w+)(\})', repl , lines)
    print lines.strip('\n')

【讨论】：

【解决方案2】：

当它仍然是一个字符串时，你正在使用 lines 变量作为匹配对象
你可以试试这个：

>>> with open('sys.infox','r') as display : #pythonic way to handle files
...     for lines in display:
...         matches = re.findall(r'(\{)(\w+)(\})', lines)
...         for match in matches:  #if there's match, it will be a list of saved groups, p.e: [('{', 'c2', '}')]
...             lines = re.sub(r'(\{)(\w+)(\})', ansiColors[match[1]] , lines)
...             print lines.strip('\n')
... 
[0.32m************************************************************
**  This is the SYS.INFO file. This file will show the    **
**  This is the SYS.INFO file. This file will show the    **
**  This is the SYS.INFO file. This file will show the    **
**  [0.37mcaller, information that you want to share, about[0.37m     **
**  [0.37mcaller, information that you want to share, about[0.37m     **
**  [0.37myour BBS.[0.37m                                             **
**  [0.37myour BBS.[0.37m

【讨论】：

感谢您提供 Pythonic 打开文件的方式并给出了很好的解释。 +1

【解决方案3】：

#!/usr/local/bin/python2.7

import sys
import re

ansiColors = {"c0" : "\033[0.30m" , "c1" : "\033[31m" , "c2" : "\033[0.32m" , "c3" : "\033[0.33m" , "c4" : "\033[0.34m" , "c5" : "\033[0.35m" , "c6" : "\033[0.36m" , "c7" : "\033[0.37m" , "c8" : "\033[1m\033[30m" , "ca" : "\033[1m\033[31m" , "cb" : "\033[1m\033[32m" , "cc" : "\033[1m\033[33m" , "cd" : "\033[1m\033[34m" , "ce" : "\033[1m\033[35m" , "cf" : "\033[1m\033[36m" , "cg" : "\033[1m\033[37m" , "R1" : "\033[41m" , "R2" : "\033[42m" , "R3" : "\033[43m" , "R4" : "\033[44m" , "R5" : "\033[45m" , "R6" : "\033[46m" , "R7" : "\033[47m"}

def replace(matchobj):
  if matchobj.group(2) in ansiColors.keys():
    return ansiColors[matchobj.group(2)]

display = open('input.txt','r')
for lines in display:
    lines = re.sub(r'(\{)(\w+)(\})', replace , lines)
    print lines.strip('\n')

使用 repl 作为函数来获取更多控制。lines.groups(2) 将导致任何结果，因为 lines 是字符串。

Output:[0.32m************************************************************
**                                                        **
**  [43m[0.37mThis is the SYS.INFO file. This file will show the[0.32m    **
**  [0.37mcaller, information that you want to share, about[0.32m     **
**  [0.37myour BBS.[0.32m                                             **
**                                                        **
************************************************************

【讨论】：