python正则表达式学习 findall

import re

text = 'to to to how are you a to to'

result = re.findall('to', text)

print(result)

正则表达式中的findall语句，可以找到字符串中所有的需要找到的内容，并且将它打印出来。

import re

text = 'to to too how are you a to to gongsunli luban'

result = re.findall('lu...', text)

print(result)

正则表达式中的模糊匹配，点可以用来表示任意字符。

import re

text = 'to to too how are you a to to gongsunli luban gongbenwuzang, wangzhe wahah,'

result = re.findall('to[a-z]', text)

print(result)

匹配必须是字母的情况， 例子：写法是[a-z]

import re

text = 'to to too how are you a to to gongsunli luban gongbenwuzang, wangzhe wahah,'

result = re.findall(' (to[a-z]) ', text)

print(result)

在正则表达式中，加上括号可以表示，不需要将单词左右两边的空格打印输出到屏幕上的情况

import re

text = 'to to too how are you a too to gongsunli luban gongbenwuzang, wangzhe wahah,'

result = re.findall(' to[a-z] ', text)
result = set(result)          # 去掉结果中重复的部分

print(result)

在正则表达式中，可以通过set语句将结果中重复的部分去掉。

import re

text = 'to to too how are you a too toooooooo gongsunli luban gongbenwuzang, wangzhe wahah,'

result = re.findall('to*', text)

print(result)

a* 可以匹配到 ’ ’ ‘a’ ‘aa’ ‘aaaa’ ‘aaaaaaaaaaaaaaaaaaaa’

import re

text = 'to to a1 too 456 153245 how are you a too toooooooo gongsunli luban gongbenwuzang, wangzhe wahah,'

result = re.findall('\d', text)

print(result)

\d表示匹配数字，且仅匹配一个数字

import re

text = 'to to a1 too 456 153245 how are you a too toooooooo gongsunli luban gongbenwuzang, wangzhe wahah,'

result = re.findall('\d+', text)

print(result)

\d+匹配在一起的数字