在列表Python中查找并替换字符串

Question

我有一张单子

nums = ['Aero', 'Base Core Newton', 'Node']

我想用Fine（即Fine Core）替换字符串基，我尝试了下面的代码，但没有效果

nums = ['Aero', 'Base Core Newton', 'Node']
nums1=[]
for i in nums:
    if 'Base' in i:
        i.replace('Base','Fine')
        nums1.append(i)

print(nums1)

我该怎么做

Answer 1

我认为你不需要把re扯进去。如果我们将OP的替换逻辑与@Ajax1234的循环结构结合使用，我们会得到：

nums = ['Aero', 'Base Core Newton', 'Node']
new_nums = [i.replace('Base','Fine') for i in nums]

结果

['Aero', 'Fine Core Newton', 'Node']

Answer 2

您可以在列表理解中使用re.sub。这样，在nums中的任何元素中处理'Base Core'的多次出现会更简单：

import re
nums = ['Aero', 'Base Core Newton', 'Node']
new_nums = [re.sub('^Base(?=\sCore)', 'Fine', i) for i in nums]

输出：

['Aero', 'Fine Core Newton', 'Node']

regex说明：

^ -> start of line anchor, anything proceeding must be at the start of the string
Base -> matches the "Base" in the string
?= -> positive lookahead, ^Base will not be matched unless the following pattern in parenthesis is found after ^Base
\sCore -> matches a single space, and then an occurrence of "Core"