如何从Python的文本文件中删除括号？

有时很难从文本文件中删除我们不需要的括号。因此， Python可以为我们做到这一点。在Python，我们可以借助正则表达式去除括号。

句法：

# import re module for using regular expression

import re

patn = re.sub(pattern, repl, sentence)

# pattern is the special RE expression for findind the brackets.

# repl is a string which replaces with the selected things by pattern

# RE is searched in sentence string

编程需要懂一点英语

用于执行我们的任务的正则表达式模式：

注意：在这里，我们使用了正则表达式的 2 个语法字符来执行此操作 -

[…] 是一个字符类，用于匹配它们之间出现的任何一个字符
\ 用于为此匹配特殊字符，我们将括号作为特殊字符

下面是它的工作原理：

示例 1：从字符串去除带有正则表达式的括号的程序

Python3

# importing re module for creating
# regex expression
import re
  
# string for passing 
text = "Welcome to geeks for geeks [GFG] A (computer science portal)"
  
# creating the regex pattern & use re.sub()
# [\([{})\]] is a RE pattern for selecting
# '{', '}', '[', ']', '(', ')' brakcets.
patn = re.sub(r"[\([{})\]]", "", text)
  
print(patn)

Python3

# importing re module for creating
# regex expression
import re
  
# reading line by line
with open('data.txt', 'r') as f:
    
    # looping the para and iterating 
    # each line
    text = f.read() 
      
    # getting the pattern for [],(),{} 
    # brackets and replace them to empty 
    # string
    # creating the regex pattern & use re.sub()
    patn = re.sub(r"[\([{})\]]", "", text) 
  
print(patn)

Python3

# importing re module for creating 
# regex expression
import re
  
# reading line by line
with open('input.txt', 'r') as f: 
    
    # store in text variable
    text = f.read() 
      
    # getting the pattern for [],(),{} 
    # brackets and replace them to empty string
    # creating the regex pattern & use re.sub()
    pattern = re.sub(r"[\([{})\]]", "", text)
  
  
# Appending the changes in new file
# It will create new file in the directory
# and write the changes in the file.
with open('output.txt', 'w') as my_file:
    my_file.write(pattern)

输出：

Welcome to geeks for geeks GFG A computer science portal

现在看起来我们的脚本运行良好。让我们在文本文件中尝试相同的操作。 Python使我们能够处理文件。

注意：有关更多信息，请参阅Python的文件处理。

示例 2：从文本文件中删除括号的程序

使用的文件：

蟒蛇3

# importing re module for creating
# regex expression
import re
  
# reading line by line
with open('data.txt', 'r') as f:
    
    # looping the para and iterating 
    # each line
    text = f.read() 
      
    # getting the pattern for [],(),{} 
    # brackets and replace them to empty 
    # string
    # creating the regex pattern & use re.sub()
    patn = re.sub(r"[\([{})\]]", "", text) 
  
print(patn)

输出：

例2：追加更改到一个新的文本文件

使用的文件：

蟒蛇3

# importing re module for creating 
# regex expression
import re
  
# reading line by line
with open('input.txt', 'r') as f: 
    
    # store in text variable
    text = f.read() 
      
    # getting the pattern for [],(),{} 
    # brackets and replace them to empty string
    # creating the regex pattern & use re.sub()
    pattern = re.sub(r"[\([{})\]]", "", text)
  
  
# Appending the changes in new file
# It will create new file in the directory
# and write the changes in the file.
with open('output.txt', 'w') as my_file:
    my_file.write(pattern)

输出：