day22 Python pickle模块

import pickle

class Car(object):

    def __init__(self, name, price):
        self.name = name
        self.price = price


c = Car("benz",100000)

# 直接将对象序列化
p = pickle.dumps(c)
print(p) # b'x80x03c__main__
Car
q ..

# 将序列化数据还原
car = pickle.loads(p)
print(car.name) # benz

# 将对象序列化之后，写入到文件中
# pickle.dump(c,open("pickle.txt",mode="wb"))
with open("pickle.txt", "wb") as f:
    pickle.dump(c, f)  
    

# 从文件中读取对象
with open("pickle.txt", "rb") as f1:
    a = pickle.load(f1)
    print(a.name)
    

# 将多个对象写入到文件中  
c1 = Car("bwm",1000)
c2 = Car("qq",2000) 

lst = [c,c1,c2]
with open("pickle.txt", "wb") as f2:
    pickle.dump(lst, f2)

with open("pickle.txt", "rb") as f2:
    a_list = pickle.load(f2)

    for duixiang in a_list:
        print("-->", duixiang.name)