class ReadWriteFile(object): '''对文件进行内容更改操作 file:文件路径,index要修改内容的行数,new_data要修改后的内容,类型为str ''' def __init__(self,file=None,index=None,new_data=None): self.file=file self.index=index-1 self.new_data=new_data def write_file(self): source_data=None with open(self.file,"r")as f: source_data=f.readlines() if " " in source_data[self.index]: blank_count=source_data[self.index].rfind(" ")+2 print(blank_count) # if self.index<=(len(source_data)) try: source_data[self.index] =str(blank_count*" ")+ self.new_data + '\n' except IndexError as error: raise IndexError(error) else: try: source_data[self.index] = self.new_data + '\n' except IndexError as error: raise IndexError(error) with open(self.file,'w')as f: for line in source_data: f.write(line) # # a='appium' # b='webdriver' # da="from %s import %s"%(a,b) # r=ReadWriteFile("/Users/liming/Desktop/appium_dir/test/__init__.py",13,"source_data = ''").write_file()