2020-05-07

1.持久化：

image.png

2.pickle:

image.png

3.举例：
from person import Person,Manager

bob=Person('Bob Smith')
sue=Person('Sue Jones','dev',10000)
tom=Manager('Tom Jones',5000)

import shelve
db = shelve.open('persondb')
for obj in (bob,sue,tom):
db[obj.name] = obj
db.close()

if name=='main':
db=shelve.open('persondb')
for key in sorted(db):
print(key,'=>',db[key])

bob1 = db['Bob Smith']
print(bob1.lastName())