提取所有行，包括包含子字符串的行以及python中子字符串之后的行

Question

I am running into problems where I am trying to extract the lines after including the line from where the substring exist.

s="""
   This is so awesome
   I need to do this more often
   This forum rocks
   Help me
  """

If the substring I search is forum , I want to get the result as

   this forum rocks
   Help me

I tried using the following statement

s.lower().split("forum",1)[1]

and my output is

forum rocks

Any help is appreciated.

Answer 1

You'll want to split the string by line, and search each line for the word you want.

s="""
This is so awesome
I need to do this more often
This forum rocks
Help me
""".split('\n')
for line in range(len(s)):
    if "forum" in s[line]:
        print(s[line])
        print(s[line+1])

As long as the multi-line string ends on the next line after the last line with text in it, you won't go out of bounds for the list. If you have the last """ on the previous line, next to Help me , you'll have to do a range check.

EDIT: Re-read the question. You want all lines after the word forum is found? The previous example I gave just gets you the next line. For all lines after the key word is found, use this:

s="""
This is so awesome
I need to do this more often
This forum rocks
Help me
""".split('\n')
found = False
for line in range(len(s-1)):
    if "forum" in s[line] or found:
        print(s[line])
        found = True

The len(s-1) part is optional. Depending on whether you want the trailing blank line included in the results. If you want that last blank line, just change it back to len(s) .

Answer 2

Try this, It will work for a string containing any number of lines.

s="""
   This is so awesome
   I need to do this more often
   This forum rocks
   Help me
  """
s=s.split('\n')
c=0
for i in s:
    if i.find("forum")!=-1: #  no match, find returns -1
        print "\n".join(s[c:])
    c+=1

Output :

This forum rocks
Help me

So, basically you find the index in the array where your match has been found and then return everything after that (by joining with a \\n as was the case in the original string).

Answer 3

One-line solution with re.search() function:

import re

s="""
   This is so awesome
   I need to do this more often
   This forum rocks
   Help me
  """    
result = re.search(r'.*\bforum[\s\S]*', s, re.M).group()
print(result)

The output:

   This forum rocks
   Help me

Answer 4

l = s.split('\n')
for n, str in enumerate(l):
    if 'forum' in str:
        print ('\n'.join(l[n:]))
        break

Output:

   This forum rocks
   Help me