print(open('persondb.dat','rb').read())
testdemo2.py
#讀取資料庫
#載入乙個例項的時候，類極其模組的檔案都必須匯入
#該類的例項再次載入的時候，對類的源**檔案的修改會自動選取
import testdemo
import shelve
db=shelve.open('persondb')
print(len(db)) #獲取資料條數 3
print(list(db.keys())) #獲取資料鍵值 ['bob smith', 'sue jones', 'tom jones']
tom=db['tom jones']
print(tom) #[manager: job=mgr, name=tom jones, pay=50000]
print(tom.lastname()) #jones
print(tom.pay) #50000
for key in db.keys():
print(key, '=>', db[key]) #列印資料庫中所有資料
for key in sorted(db, reverse=true):
print(key, '=>', db[key]) #列印資料庫中所有資料，並且排序
db.close()
testdemo3.py
#更新shelve中的物件
import shelve
db=shelve.open('persondb')
sue=db['sue jones']
print(sue) #[person: job=dev, name=sue jones, pay=10000],每次執行值都會儲存
sue.giveraist(1.1)
db['sue jones']=sue
print(sue) #[person: job=dev, name=sue jones, pay=21000] pay為最新的值,每次執行值都會變化
db.close()
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