python 替换重复字符_Python搜索和替换是重复替换字符串？

我有以下代码循环浏览文件夹中的文件并进行简单的搜索和替换，然后将结果输出到不同的文件夹。我注意到替换字符串似乎被应用了两次。

例如：

Search string: foo

Replace string: foo bar

Result: foo bar bar

这是我的代码。我相信问题很明显，但我不能把它放在手上。

def SearchReplace(directory, search, replace, filePattern):

for path, dirs, files in os.walk(os.path.abspath(directory)):

for filename in fnmatch.filter(files, filePattern):

filepath = os.path.join(path, filename)

outfile = os.path.join(outputdir, filename)

with open(filepath) as f:

s = f.read()

s = s.replace(search, replace)

with open(outfile, "w") as f:

f.write(s)

SearchReplace(inputdir, searchstr, replacestr, ext)注：如果我不输出结果到一个单独的文件夹，搜索/替换按预期方式执行。意思是，下面的代码工作正常(修改输入文件在同一文件夹中)：

def SearchReplace(directory, search, replace, filePattern):

for path, dirs, files in os.walk(os.path.abspath(directory)):

for filename in fnmatch.filter(files, filePattern):

filepath = os.path.join(path, filename)

with open(filepath) as f:

s = f.read()

s = s.replace(search, replace)

with open(filepath, "w") as f:

f.write(s)

SearchReplace(inputdir, searchstr, replacestr, ext)但是，我需要将结果输出到单独的文件夹。