python string search replace

问题:

SSViewer::set_theme('bullsorbit'); 

this my string. I want search in string "SSViewer::set_theme('bullsorbit'); " and replace 'bullsorbit' with another string. 'bullsorbit' string is dynamically changing.

回答1:

Not in a situation to be able to test this so you may need to fiddle with the Regular Expression (they may be errors in it.)

import re
re.sub("SSViewer::set_theme\('[a-z]+'\)", "SSViewer::set_theme('whatever')", my_string)

Is this what you want?

Just tested it, this is some sample output:

my_string = """Some file with some other junk
SSViewer::set_theme('bullsorbit');
SSViewer::set_theme('another');
Something else"""

import re
replaced = re.sub("SSViewer::set_theme\('[a-z]+'\)", "SSViewer::set_theme('whatever')", my_string)
print replaced

produces:

Some file with some other junk
SSViewer::set_theme('whatever');
SSViewer::set_theme('whatever');
Something else

if you want to do it to a file:

my_string = open('myfile', 'r').read()

回答2:

>> my_string = "SSViewer::set_theme('bullsorbit');"
>>> import re
>>> change = re.findall(r"SSViewer::set_theme\('(\w*)'\);",my_string)
>>> my_string.replace(change[0],"blah")
"SSViewer::set_theme('blah');"

its not elegant but it works. the findall will return a dictionary of items that are inside the ('') and then replaces them. If you can get sub to work then that may look nicer but this will definitely work

回答3:

st = "SSViewer::set_theme('"
for line in open("file.txt"):
    line=line.strip()
    if st in line:
        a = line[ :line.index(st)+len(st)]
        b = line [line.index(st)+len(st): ]
        i = b.index("')")
        b = b[i:]
        print a + "newword" + b

回答4:

while your explanation is not entirely clear, I think you might make some use of the following:

open(fname).read().replace('bullsorbit', 'new_string')