python3 pickle, json

pickle 有dump ,dumps ,load,loads等方法。区别在于dumps不会写入到文件。

import pickle

string = ['a', 2341, 'adsf']

p_str= pickle.dumps(string)
print(p_str)
l_str = pickle.loads(p_str)
print(l_str)

p_str1 = 'This is a test!'
with open('d:/python/pydev/day3/src/p.pkl', 'wb') as file:
    pickle.dump(p_str1, file)

with open('d:/python/pydev/day3/src/p.pkl', 'rb' ) as file1:  
    l_file = pickle.load(file1)

print(l_file)

结果如下：

b'x80x03]qx00(Xx01x00x00x00aqx01M% Xx04x00x00x00adsfqx02e.'
['a', 2341, 'adsf']
This is a test!

'''
The file argument must have a write() method that accepts a single bytes argument.
It can thus be an on-disk file opened for binary writing
'''

注意：pickle以二进制处理，所以文件打开方式应该加上b, 如'wb'.'rb'如果仅以w方式打开则会报错，这里可能理解有误，奇怪的是json用wb会报错，而w则正常。

import json

string = ['a', 2341, 'adsf']

p_str= json.dumps(string)
print(p_str)
l_str = json.loads(p_str)
print(l_str)

p_str1 = 'This is a test!'
with open('d:/python/pydev/day3/src/p.pkl', 'w') as file:
    json.dump(p_str1, file)

with open('d:/python/pydev/day3/src/p.pkl', 'r' ) as file1:  
    l_file = json.load(file1)

print(l_file)

运行结果：

["a", 2341, "adsf"]
['a', 2341, 'adsf']
This is a test!

pickle是python特有的，而json支持语言很多。另外json dump的结果是可以直接读的，pickle则不行。