python - 使用正则表达式对给定的字符串进行分区

Question

尝试将字符串分成两部分。

#Need to get 'I1234' and 'I56/I78'
name1 = 'I1234/I56/I78'

#Need to get '\I1234 ' and 'I56/I78'
name2 = '\I1234 /I56/I78'      

#Need to get '\I1234 ' and '\I56 /I78'
name3 = '\I1234 /\I56 /I78'

#Need to get '\1234 ' and '\I56 /\I78 '
name4 = '\I1234 /\I56 /\I78 '

我试过了，成功了:

pat_a = re.compile(r'(.+)(/)(.+)')

Is there a better way ?

result = re.findall(pat_a, name2[::-1])

编辑

可能还有更复杂的字符串，例如:

\I78_[0]/abcd_/efg_ /I1234/I56

Answer 1

不确定是否更好，但您可以使用 partition 或 split 并设置 maxsplit=1 以避免 re 模块导入:

print('I1234/I56/I78'.partition("/"))   # ('I1234', '/', 'I56/I78')

print('I1234/I56/I78'.split("/",1))     # ['I1234', 'I56/I78']

对于 partition，您需要查看元组的第 0 个和第 2 个索引:

first, _ , last = 'I1234/I56/I78'.partition("/")

独库:

• https://docs.python.org/3/library/stdtypes.html#str.partition
• https://docs.python.org/3/library/stdtypes.html#str.split

---

完整示例:

name1 = 'I1234/I56/I78' 
name2 = '\I1234 /I56/I78'       
name3 = '\I1234 /\I56 /I78' 
name4 = '\I1234 /\I56 /\I78 '

for n in [name1,name2,name3,name4]:
    print(n.partition("/"))   # ('I1234', '/', 'I56/I78')
    print(n.split("/",1))     # ['I1234', 'I56/I78']

输出(反斜杠被转义 - 这就是它们加倍的原因):

('I1234', '/', 'I56/I78')           # using partition
['I1234', 'I56/I78']                # using split

('\\I1234 ', '/', 'I56/I78')        # partition
['\\I1234 ', 'I56/I78']             # split .. etc.

('\\I1234 ', '/', '\\I56 /I78')
['\\I1234 ', '\\I56 /I78']

('\\I1234 ', '/', '\\I56 /\\I78 ')
['\\I1234 ', '\\I56 /\\I78 ']