从字符串中提取 substring 和 x 字符

Question

I have a string:

desc = 'Communication is a cornerstone of society. It is the expression of people who want to feel connected and share their thoughts, interests and feelings with one another. And telecommunication allows us to interact even when we are in different places and separated by a distance.'

If a specific substring is in desc i want to extract that substring and also the next x characters after it.

Ex:

if 'telecommunication' in desc :
     specific_desc = 'telecommunication allows us to interact'

if 'society' in desc:
     specific_desc = 'society. It is the expression of people who want to feel connected and 
                      share their thoughts'

I don't know how to get the x characters after the specific substring.

Answer 1

You can do something like this, You can use index slicing.

string = 'Communication is a cornerstone of society'

substring = 'Communication'

x = 15

if substring in string:
    index = string.find(substring)
    print(string[index:index + x])

Answer 2

You can use the index() or find() to get the starting position of the substring, and then slicing to get the characters you want.

def get_sub_x(full, sub, x):
   try:
      index = full.index(sub)
      return full[index: index + len(sub) + x]
   except ValueError:
      return None

print(get_sub_x('Hello World', 'Wo', 2))

Outputs Worl

Answer 3

Try this

n = 15
keyword = "society"

found = re.search(f"({keyword}.*)", desc).group(0)
found = found[len(keyword) + n]
print(found)

# 'society. It is the expression of people who want to feel connected and share their thoughts, interests and feelings with one another. And telecommunication allows us to interact even when we are in different places and separated by a distance.'

Answer 4

def get_index (string):
    if string in desc:
        return desc.index (string)

start = get_index ('telecommunications ')
end = get_index ('even')
print (desc [start:end])