In my previous blog, I wrote the code to replace all string in a file: http://leons.im/2011/02/replace-all-strings-in-a-file/. Today, I write a cooler code – It can replace all strings in many files, actually it can replace all strings in files that are in a same folder.

Save the following code to the folder that you want to replace strings, and name it like replace.py.

Modify parameters from_str, to_str and files_to_replace in the form of regular expression. Then run python replace.py.

``` python Replace Strings for All Files in a Folder
#!/usr/bin/python import sys, os, re #Created by Leon on Aug 9, 2012

from_str = r’\t’ to_str = r’ ‘ files_to_replace = r’.(h|m|mm|cpp|inl|def|txt|php|tpl|css|js|py)$’

def replace(infile, outfile): f1 = open(infile) f0 = open(outfile, ‘w’) data = f1.readlines() for line in data: f0.write(re.sub(from_str, to_str, line)) f1.close() f0.close()

def walk_folder(path): print “Current Path: “ + path for dirpath, dirs, files in os.walk(path): for filename in files: if re.search(files_to_replace, filename): print “—-“ + filename + “….” fi = open(os.path.join(dirpath, filename)) fo = open(os.path.join(dirpath, filename + “.bk”), ‘w’) fo.write(fi.read()) fo.close() fi.close() replace(os.path.join(dirpath, filename + “.bk”), os.path.join(dirpath, filename)) print “Done.” os.remove(os.path.join(dirpath, filename + “.bk”))

if name == ‘main’: path = os.path.abspath(os.path.dirname(sys.argv[0])) walk_folder(path) print print “All files have been translated successfully.” print print “Created for you by Leon on Aug 9, 2012.” raw_input() ```