python3 pickle, json

Posted 2020-06-28 安迪_963

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

 1 import pickle
 2 
 3 string = [‘a‘, 2341, ‘adsf‘]
 4 
 5 p_str= pickle.dumps(string)
 6 print(p_str)
 7 l_str = pickle.loads(p_str)
 8 print(l_str)
 9 
10 p_str1 = ‘This is a test!‘
11 with open(‘d:/python/pydev/day3/src/p.pkl‘, ‘wb‘) as file:
12     pickle.dump(p_str1, file)
13 
14 with open(‘d:/python/pydev/day3/src/p.pkl‘, ‘rb‘ ) as file1:  
15     l_file = pickle.load(file1)
16 
17 print(l_file)

pickle

结果如下：

b‘\x80\x03]q\x00(X\x01\x00\x00\x00aq\x01M%\tX\x04\x00\x00\x00adsfq\x02e.‘
[‘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。

 1 import json
 2 
 3 string = [‘a‘, 2341, ‘adsf‘]
 4 
 5 p_str= json.dumps(string)
 6 print(p_str)
 7 l_str = json.loads(p_str)
 8 print(l_str)
 9 
10 p_str1 = ‘This is a test!‘
11 with open(‘d:/python/pydev/day3/src/p.pkl‘, ‘w‘) as file:
12     json.dump(p_str1, file)
13 
14 with open(‘d:/python/pydev/day3/src/p.pkl‘, ‘r‘ ) as file1:  
15     l_file = json.load(file1)
16 
17 print(l_file)

json

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。