你能帮我做这个例子吗?
如果存在,我想加载一个序列化的字典,修改它并再次转储它。我想我用来打开文件的模式有问题,但我不知道正确的方法。
import os
import cPickle as pickle
if os.path.isfile('file.txt'):
cache_file = open('file.txt', 'rwb')
cache = pickle.load(cache_file)
else:
cache_file = open('file.txt', 'wb')
cache = dict.fromkeys([1,2,3])
# modifications of cache
pickle.dump(cache, cache_file)
cache_file.close()
运行两次以查看错误:
Traceback (most recent call last):
File "example.py", line 11, in <module>
pickle.dump(cache, cache_file)
IOError: [Errno 9] Bad file descriptor