删除包含特定字符串的行

Question

我正在尝试从文本文件中读取文本,读取行,删除包含特定字符串的行(在本例中为"bad"和"naughty").我写的代码是这样的:

infile = file('./oldfile.txt')

newopen = open('./newfile.txt', 'w')
for line in infile :

    if 'bad' in line:
        line = line.replace('.' , '')
    if 'naughty' in line:
        line = line.replace('.', '')
    else:
        newopen.write(line)

newopen.close()

我这样写了但是没有用.

一件重要的事情是,如果文本的内容是这样的:

good baby
bad boy
good boy
normal boy

我不希望输出有空行.所以不喜欢:

good baby

good boy
normal boy

但像这样:

good baby
good boy
normal boy

我应该从上面的代码中编辑什么？

Answer 1

您可以使代码更简单,更易读

bad_words = ['bad', 'naughty']

with open('oldfile.txt') as oldfile, open('newfile.txt', 'w') as newfile:
    for line in oldfile:
        if not any(bad_word in line for bad_word in bad_words):
            newfile.write(line)

使用Context Manager和任何.

Answer 2

您可以不将该行包含在新文件中而不是替换.

for line in infile :
     if 'bad' not in line and 'naughty' not in line:
            newopen.write(line)

Answer 3

我用它来从文本文件中删除不需要的单词：

bad_words = ['abc', 'def', 'ghi', 'jkl']

with open('List of words.txt') as badfile, open('Clean list of words.txt', 'w') as cleanfile:
    for line in badfile:
        clean = True
        for word in bad_words:
            if word in line:
                clean = False
        if clean == True:
            cleanfile.write(line)

或对目录中的所有文件执行相同的操作：

import os

bad_words = ['abc', 'def', 'ghi', 'jkl']

for root, dirs, files in os.walk(".", topdown = True):
    for file in files:
        if '.txt' in file:
            with open(file) as filename, open('clean '+file, 'w') as cleanfile:
                for line in filename:
                    clean = True
                    for word in bad_words:
                        if word in line:
                            clean = False
                    if clean == True:
                        cleanfile.write(line)

我敢肯定必须有一种更优雅的方法来做到这一点，但这确实达到了我想要的目的。