本文实例讲述了python实现的用于搜索文件并进行内容替换的类。分享给大家供大家参考。具体实现方法如下：
#!/usr/bin/python -o
# coding: utf-8
“””
-replace string in files (recursive)
-display the difference.
v0.2
– search_string can be a re.compile() object -> use re.sub for replacing
v0.1
– initial version
useable by a small “client” script, e.g.:
——————————————————————————-
#!/usr/bin/python -o
# coding: utf-8
import sys, re
#sys.path.insert(0,”/path/to/git/repro/”) # please change path
from replace_in_files import searchandreplace
searchandreplace(
search_path = “/to/the/files/”,
# e.g.: simple string replace:
search_string = ‘the old string’,
replace_string = ‘the new string’,
# e.g.: regular expression replacing (used re.sub)
#search_string = re.compile(‘{% url (.*?) %}’),
#replace_string = “{% url ‘\g’ %}”,
search_only = true, # display only the difference
#search_only = false, # write the new content
file_filter=(“*.py”,), # fnmatch-filter
)
——————————————————————————-
:copyleft: 2009-2011 by jens diemer
“””
__author__ = “jens diemer”
__license__ = “””gnu general public license v3 or above –
http://www.opensource.org/licenses/gpl-license.php”””
__url__ = “http://www.jensdiemer.de”
__version__ = “0.2”
import os, re, time, fnmatch, difflib
# fixme: see http://stackoverflow.com/questions/4730121/cant-get-an-objects-class-name-in-python
re_type = type(re.compile(“”))
class searchandreplace(object):
def __init__(self, search_path, search_string, replace_string,
search_only=true, file_filter=(“*.*”,)):
self.search_path = search_path
self.search_string = search_string
self.replace_string = replace_string
self.search_only = search_only
self.file_filter = file_filter
assert isinstance(self.file_filter, (list, tuple))
# fixme: see http://stackoverflow.com/questions/4730121/cant-get-an-objects-class-name-in-python
self.is_re = isinstance(self.search_string, re_type)
print “search ‘%s’ in [%s]…” % (
self.search_string, self.search_path
)
print “_” * 80
time_begin = time.time()
file_count = self.walk()
print “_” * 80
print “%s files searched in %0.2fsec.” % (
file_count, (time.time() – time_begin)
)
def walk(self):
file_count = 0
for root, dirlist, filelist in os.walk(self.search_path):
if “.svn” in root:
continue
for filename in filelist:
for file_filter in self.file_filter:
if fnmatch.fnmatch(filename, file_filter):
self.search_file(os.path.join(root, filename))
file_count += 1
return file_count
def search_file(self, filepath):
f = file(filepath, “r”)
old_content = f.read()
f.close()
if self.is_re or self.search_string in old_content:
new_content = self.replace_content(old_content, filepath)
if self.is_re and new_content == old_content:
return
print filepath
self.display_plaintext_diff(old_content, new_content)
def replace_content(self, old_content, filepath):
if self.is_re:
new_content = self.search_string.sub(self.replace_string, old_content)
if new_content == old_content:
return old_content
else:
new_content = old_content.replace(
self.search_string, self.replace_string
)
if self.search_only != false:
return new_content
print “write new content into %s…” % filepath,
try:
f = file(filepath, “w”)
f.write(new_content)
f.close()
except ioerror, msg:
print “error:”, msg
else:
print “ok”
print
return new_content
def display_plaintext_diff(self, content1, content2):
“””
display a diff.
“””
content1 = content1.splitlines()
content2 = content2.splitlines()
diff = difflib.differ().compare(content1, content2)
def is_diff_line(line):
for char in (“-“, “+”, “?”):
if line.startswith(char):
return true
return false
print “line | text\n——————————————-”
old_line = “”
in_block = false
old_lineno = lineno = 0
for line in diff:
if line.startswith(” “) or line.startswith(“+”):
lineno += 1
if old_lineno == lineno:
display_line = “%4s | %s” % (“”, line.rstrip())
else:
display_line = “%4s | %s” % (lineno, line.rstrip())
if is_diff_line(line):
if not in_block:
print “…”
# display previous line
print old_line
in_block = true
print display_line
else:
if in_block:
# display the next line aber a diff-block
print display_line
in_block = false
old_line = display_line
old_lineno = lineno
print “…”
if __name__ == “__main__”:
searchandreplace(
search_path=”.”,
# e.g.: simple string replace:
search_string=’the old string’,
replace_string=’the new string’,
# e.g.: regular expression replacing (used re.sub)
#search_string = re.compile(‘{% url (.*?) %}’),
#replace_string = “{% url ‘\g’ %}”,
search_only=true, # display only the difference
# search_only = false, # write the new content
file_filter=(“*.py”,), # fnmatch-filter
)
希望本文所述对大家的python程序设计有所帮助。