Python有string.find()和string.rfind()来获取字符串中子字符串的索引。

我想知道是否有像string.find_all()这样的东西可以返回所有找到的索引(不仅是从开始的第一个索引,还是从结束的第一个索引)。

例如:

string = "test test test test"

print string.find('test') # 0
print string.rfind('test') # 15

#this is the goal
print string.find_all('test') # [0,5,10,15]

要统计出现次数,请参见计算字符串中子字符串出现的次数。


当前回答

这是我使用re.finditer的技巧

import re

text = 'This is sample text to test if this pythonic '\
       'program can serve as an indexing platform for '\
       'finding words in a paragraph. It can give '\
       'values as to where the word is located with the '\
       'different examples as stated'

#  find all occurances of the word 'as' in the above text

find_the_word = re.finditer('as', text)

for match in find_the_word:
    print('start {}, end {}, search string \'{}\''.
          format(match.start(), match.end(), match.group()))

其他回答

如果你想使用没有re(regex),那么:

find_all = lambda _str,_w : [ i for i in range(len(_str)) if _str.startswith(_w,i) ]

string = "test test test test"
print( find_all(string, 'test') ) # >>> [0, 5, 10, 15]

这个帖子有点老了,但对我来说很管用:

numberString = "onetwothreefourfivesixseveneightninefiveten"
testString = "five"

marker = 0
while marker < len(numberString):
    try:
        print(numberString.index("five",marker))
        marker = numberString.index("five", marker) + 1
    except ValueError:
        print("String not found")
        marker = len(numberString)

你可以试试:

>>> string = "test test test test"
>>> for index,value in enumerate(string):
    if string[index:index+(len("test"))] == "test":
        print index

0
5
10
15

请看看下面的代码

#!/usr/bin/env python
# coding:utf-8
'''黄哥Python'''


def get_substring_indices(text, s):
    result = [i for i in range(len(text)) if text.startswith(s, i)]
    return result


if __name__ == '__main__':
    text = "How much wood would a wood chuck chuck if a wood chuck could chuck wood?"
    s = 'wood'
    print get_substring_indices(text, s)
def find_index(string, let):
    enumerated = [place  for place, letter in enumerate(string) if letter == let]
    return enumerated

例如:

find_index("hey doode find d", "d") 

返回:

[4, 7, 13, 15]