例子:
>>> convert('CamelCase')
'camel_case'
例子:
>>> convert('CamelCase')
'camel_case'
当前回答
轻度改编自https://stackoverflow.com/users/267781/matth 谁使用发电机。
def uncamelize(s):
buff, l = '', []
for ltr in s:
if ltr.isupper():
if buff:
l.append(buff)
buff = ''
buff += ltr
l.append(buff)
return '_'.join(l).lower()
其他回答
就我个人而言,我不确定在python中使用正则表达式的任何东西都可以被描述为优雅。这里的大多数答案只是做“代码高尔夫”类型的RE技巧。优雅的编码应该是容易理解的。
def to_snake_case(not_snake_case):
final = ''
for i in xrange(len(not_snake_case)):
item = not_snake_case[i]
if i < len(not_snake_case) - 1:
next_char_will_be_underscored = (
not_snake_case[i+1] == "_" or
not_snake_case[i+1] == " " or
not_snake_case[i+1].isupper()
)
if (item == " " or item == "_") and next_char_will_be_underscored:
continue
elif (item == " " or item == "_"):
final += "_"
elif item.isupper():
final += "_"+item.lower()
else:
final += item
if final[0] == "_":
final = final[1:]
return final
>>> to_snake_case("RegularExpressionsAreFunky")
'regular_expressions_are_funky'
>>> to_snake_case("RegularExpressionsAre Funky")
'regular_expressions_are_funky'
>>> to_snake_case("RegularExpressionsAre_Funky")
'regular_expressions_are_funky'
这么多复杂的方法…… 只需找到所有“标题”组,并加入其小写变体与下划线。
>>> import re
>>> def camel_to_snake(string):
... groups = re.findall('([A-z0-9][a-z]*)', string)
... return '_'.join([i.lower() for i in groups])
...
>>> camel_to_snake('ABCPingPongByTheWay2KWhereIsOurBorderlands3???')
'a_b_c_ping_pong_by_the_way_2_k_where_is_our_borderlands_3'
如果你不想让数字像组的第一个字符或单独的组-你可以使用([A-z][a-z0-9]*)掩码。
没有任何库:
def camelify(out):
return (''.join(["_"+x.lower() if i<len(out)-1 and x.isupper() and out[i+1].islower()
else x.lower()+"_" if i<len(out)-1 and x.islower() and out[i+1].isupper()
else x.lower() for i,x in enumerate(list(out))])).lstrip('_').replace('__','_')
有点重,但是
CamelCamelCamelCase -> camel_camel_camel_case
HTTPRequest -> http_request
GetHTTPRequest -> get_http_request
getHTTPRequest -> get_http_request
这个网站上提出了非常好的RegEx:
(?<!^)(?=[A-Z])
如果python有一个字符串分割方法,它应该工作…
在Java中:
String s = "loremIpsum";
words = s.split("(?<!^)(?=[A-Z])");
以下是我的解决方案:
def un_camel(text):
""" Converts a CamelCase name into an under_score name.
>>> un_camel('CamelCase')
'camel_case'
>>> un_camel('getHTTPResponseCode')
'get_http_response_code'
"""
result = []
pos = 0
while pos < len(text):
if text[pos].isupper():
if pos-1 > 0 and text[pos-1].islower() or pos-1 > 0 and \
pos+1 < len(text) and text[pos+1].islower():
result.append("_%s" % text[pos].lower())
else:
result.append(text[pos].lower())
else:
result.append(text[pos])
pos += 1
return "".join(result)
它支持评论中讨论的那些极端情况。例如,它会像它应该的那样将getHTTPResponseCode转换为get_http_response_code。