【python】re库 正则的一些过滤和把str拆分成list案例 以及json dict类型
0x01:
部分参考:https://www.cnblogs.com/edwardsun/p/4421773.html
- match(string[, pos[, endpos]]) | re.match(pattern, string[, flags]): 这个方法将从string的pos下标处起尝试匹配pattern;如果pattern结束时仍可匹配,则返回一个Match对象;如果匹配过程中pattern无法匹配,或者匹配未结束就已到达endpos,则返回None。 pos和endpos的默认值分别为0和len(string);re.match()无法指定这两个参数,参数flags用于编译pattern时指定匹配模式。 注意:这个方法并不是完全匹配。当pattern结束时若string还有剩余字符,仍然视为成功。想要完全匹配,可以在表达式末尾加上边界匹配符'$'。 示例参见2.1小节。
- search(string[, pos[, endpos]]) | re.search(pattern, string[, flags]): 这个方法用于查找字符串中可以匹配成功的子串。从string的pos下标处起尝试匹配pattern,如果pattern结束时仍可匹配,则返回一个Match对象;若无法匹配,则将pos加1后重新尝试匹配;直到pos=endpos时仍无法匹配则返回None。 pos和endpos的默认值分别为0和len(string));re.search()无法指定这两个参数,参数flags用于编译pattern时指定匹配模式。
12345678910111213141516
# encoding: UTF-8
import
re
# 将正则表达式编译成Pattern对象
pattern
=
re.
compile
(r
'world'
)
# 使用search()查找匹配的子串,不存在能匹配的子串时将返回None
# 这个例子中使用match()无法成功匹配
match
=
pattern.search(
'hello world!'
)
if
match:
# 使用Match获得分组信息
print
match.group()
### 输出 ###
# world
- split(string[, maxsplit]) | re.split(pattern, string[, maxsplit]): 按照能够匹配的子串将string分割后返回列表。maxsplit用于指定最大分割次数,不指定将全部分割。
1234567
import
re
p
=
re.
compile
(r
'\d+'
)
print
p.split(
'one1two2three3four4'
)
### output ###
# ['one', 'two', 'three', 'four', '']
- findall(string[, pos[, endpos]]) | re.findall(pattern, string[, flags]): 搜索string,以列表形式返回全部能匹配的子串。
1234567
import
re
p
=
re.
compile
(r
'\d+'
)
print
p.findall(
'one1two2three3four4'
)
### output ###
# ['1', '2', '3', '4']
- finditer(string[, pos[, endpos]]) | re.finditer(pattern, string[, flags]): 搜索string,返回一个顺序访问每一个匹配结果(Match对象)的迭代器。
12345678
import
re
p
=
re.
compile
(r
'\d+'
)
for
m
in
p.finditer(
'one1two2three3four4'
):
print
m.group(),
### output ###
# 1 2 3 4
- sub(repl, string[, count]) | re.sub(pattern, repl, string[, count]): 使用repl替换string中每一个匹配的子串后返回替换后的字符串。 当repl是一个字符串时,可以使用\id或\g<id>、\g<name>引用分组,但不能使用编号0。 当repl是一个方法时,这个方法应当只接受一个参数(Match对象),并返回一个字符串用于替换(返回的字符串中不能再引用分组)。 count用于指定最多替换次数,不指定时全部替换。
123456789101112131415
import
re
p
=
re.
compile
(r
'(\w+) (\w+)'
)
s
=
'i say, hello world!'
print
p.sub(r
'\2 \1'
, s)
def
func(m):
return
m.group(
1
).title()
+
' '
+
m.group(
2
).title()
print
p.sub(func, s)
### output ###
# say i, world hello!
# I Say, Hello World!
- subn(repl, string[, count]) |re.sub(pattern, repl, string[, count]): 返回 (sub(repl, string[, count]), 替换次数)。
123456789101112131415
import
re
p
=
re.
compile
(r
'(\w+) (\w+)'
)
s
=
'i say, hello world!'
print
p.subn(r
'\2 \1'
, s)
def
func(m):
return
m.group(
1
).title()
+
' '
+
m.group(
2
).title()
print
p.subn(func, s)
### output ###
# ('say i, world hello!', 2)
# ('I Say, Hello World!', 2)
0x02:自己的案例
需要对前端传来的
str数据切分成list
然后传给数据库
原数据:
{"value":"123","isEditing":false,"isActive":false,"isChecked":false},{"value":"2","isEditing":false,"isActive":false,"isChecked":false},{"value":"32","isEditing":false,"isActive":false,"isChecked":false},{"value":"12","isEditing":false,"isActive":false,"isChecked":false},{"value":"12","isEditing":false,"isActive":false,"isChecked":false},{"value":"123","isEditing":false,"isActive":false,"isChecked":false},{"value":"32","isEditing":false,"isActive":false,"isChecked":false},{"value":"23","isEditing":false,"isActive":false,"isChecked":false},{"value":"12","isEditing":false,"isActive":false,"isChecked":false},{"value":"321","isEditing":false,"isActive":false,"isChecked":false},{"value":"21","isEditing":false,"isActive":false,"isChecked":false}]
过滤:
str = text def checkFilter(keywords,text): return re.sub('|'.join(keywords),'',str) keywords = ('\'','"','\[{','\}]','\{') a = checkFilter(keywords,text) print (checkFilter(keywords,text))
输出结果:
<class 'str'> ****************** value:123,isEditing:false,isActive:false,isChecked:false},value:2,isEditing:false,isActive:false,isChecked:false},value:32,isEditing:false,isActive:false,isChecked:false},value:12,isEditing:false,isActive:false,isChecked:false},value:12,isEditing:false,isActive:false,isChecked:false},value:123,isEditing:false,isActive:false,isChecked:false},value:32,isEditing:false,isActive:false,isChecked:false},value:23,isEditing:false,isActive:false,isChecked:false},value:12,isEditing:false,isActive:false,isChecked:false},value:321,isEditing:false,isActive:false,isChecked:false},value:21,isEditing:false,isActive:false,isChecked:false
拆分:
b = a.split('},') print(b)
输出结果:
****************** ['value:123,isEditing:false,isActive:false,isChecked:false', 'value:2,isEditing:false,isActive:false,isChecked:false', 'value:32,isEditing:false,isActive:false,isChecked:false', 'value:12,isEditing:false,isActive:false,isChecked:false', 'value:12,isEditing:false,isActive:false,isChecked:false', 'value:123,isEditing:false,isActive:false,isChecked:false', 'value:32,isEditing:false,isActive:false,isChecked:false', 'value:23,isEditing:false,isActive:false,isChecked:false', 'value:12,isEditing:false,isActive:false,isChecked:false', 'value:321,isEditing:false,isActive:false,isChecked:false', 'value:21,isEditing:false,isActive:false,isChecked:false'] ******************
源码:
import re input = open('I:\\python_test\\json_mysql\\jsondata.txt','r') text=input.read() print (text) print ('******************') print (type(text)) print ('******************') str = text def checkFilter(keywords,text): return re.sub('|'.join(keywords),'',str) keywords = ('\'','"','\[{','\}]','\{') a = checkFilter(keywords,text) print (checkFilter(keywords,text)) print ('******************') b = a.split('},') print(b) print ('******************') print (type(b)) print ('******************') print (b[0]) print ('******************') str1 = b[0] b1 = str1.split(':') print (b1[0])
输出:
[{"value":"123","isEditing":false,"isActive":false,"isChecked":false},{"value":"2","isEditing":false,"isActive":false,"isChecked":false},{"value":"32","isEditing":false,"isActive":false,"isChecked":false},{"value":"12","isEditing":false,"isActive":false,"isChecked":false},{"value":"12","isEditing":false,"isActive":false,"isChecked":false},{"value":"123","isEditing":false,"isActive":false,"isChecked":false},{"value":"32","isEditing":false,"isActive":false,"isChecked":false},{"value":"23","isEditing":false,"isActive":false,"isChecked":false},{"value":"12","isEditing":false,"isActive":false,"isChecked":false},{"value":"321","isEditing":false,"isActive":false,"isChecked":false},{"value":"21","isEditing":false,"isActive":false,"isChecked":false}] ****************** <class 'str'> ****************** value:123,isEditing:false,isActive:false,isChecked:false},value:2,isEditing:false,isActive:false,isChecked:false},value:32,isEditing:false,isActive:false,isChecked:false},value:12,isEditing:false,isActive:false,isChecked:false},value:12,isEditing:false,isActive:false,isChecked:false},value:123,isEditing:false,isActive:false,isChecked:false},value:32,isEditing:false,isActive:false,isChecked:false},value:23,isEditing:false,isActive:false,isChecked:false},value:12,isEditing:false,isActive:false,isChecked:false},value:321,isEditing:false,isActive:false,isChecked:false},value:21,isEditing:false,isActive:false,isChecked:false ****************** ['value:123,isEditing:false,isActive:false,isChecked:false', 'value:2,isEditing:false,isActive:false,isChecked:false', 'value:32,isEditing:false,isActive:false,isChecked:false', 'value:12,isEditing:false,isActive:false,isChecked:false', 'value:12,isEditing:false,isActive:false,isChecked:false', 'value:123,isEditing:false,isActive:false,isChecked:false', 'value:32,isEditing:false,isActive:false,isChecked:false', 'value:23,isEditing:false,isActive:false,isChecked:false', 'value:12,isEditing:false,isActive:false,isChecked:false', 'value:321,isEditing:false,isActive:false,isChecked:false', 'value:21,isEditing:false,isActive:false,isChecked:false'] ****************** <class 'list'> ****************** value:123,isEditing:false,isActive:false,isChecked:false ****************** value
2910.1.14-------------------------------------------------------------------------------------------------------
拼接dict类型 json
----------------------------------------------------------------------------------------------------------------
b = a.split('},') print(b) print ('******************') print (type(b)) print ('******************') print (b[0]) print (type(b[0])) print ('******************') lines_json = b[0].replace(',', '","')#替换字符;;;;;具体b[i] for输出到数据库 lines_json1 = lines_json.replace(':','":"') lines_json2 = ('{"'+lines_json1+'"}') print (lines_json2) print ('******************') j = json.loads(lines_json2) print (j) print (j["value"]) print(type(j))
输出:
****************** <class 'list'> ****************** value:123,isEditing:false,isActive:false,isChecked:false <class 'str'> ****************** {"value":"123","isEditing":"false","isActive":"false","isChecked":"false"} ****************** {'isActive': 'false', 'value': '123', 'isEditing': 'false', 'isChecked': 'false'} 123 <class 'dict'>
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