python写一段脚本代码自动完成输入（目录下的所有）文件的数据替换（修改数据和替换数据都是输入的）【转】

转自：http://blog.csdn.net/lixiaojie1012/article/details/23628129

1. 初次尝试python语言，感觉用着真舒服，简单明了，库函数一调用就OK了
   
   [python] view plain copy 在CODE上查看代码片派生到我的代码片
   import sys,os,os.path
   def file_replace():
       path = sys.argv[1]
       old_data = sys.argv[2]
       new_data = sys.argv[3]
       if not os.path.exists(path):
           print 'file of dir does not exists!\n'
           return
       elif os.path.isdir(path):
           for root,dirs,files in os.walk(path):
               for fn in files:
                   filepath = os.path.join(root,fn)
                   f = open(filepath,'r+')
                   line = f.readlines()
                   f.seek(0)
                   for s in line:
                       f.write(s.replace(old_data,new_data))
                   f.close()
       elif os.path.isfile(path):
           f = open(path,'r+')
           line = f.readlines()
           f.seek(0)
           for s in line:
               f.write(s.replace(old_data,new_data))
           f.close()
       else:
           print 'argv[1] illegal,not a file or dir\n'
           return
   if __name__=='__main__':
       file_replace()