看一下这个问题。那里有一些解决方案。
尽管我可能会以Daniel和MAK所建议的相同方式进行操作-也许要上课以使事情更加灵活和明确：
class Prepender: def __init__(self, fname, mode='w'): self.__write_queue = [] self.__f = open(fname, mode) def write(self, s): self.__write_queue.insert(0, s) def close(self): self.__exit__(None, None, None) def __enter__(self): return self def __exit__(self, type, value, traceback): if self.__write_queue: self.__f.writelines(self.__write_queue) self.__f.close()with Prepender('test_d.out') as f: f.write('string 1n') f.write('string 2n') f.write('string 3n')
