我有错误 'Attempt to use a closed connection.'

Question

我的代码有一些问题。所以，我想通过在表单中写入数据来将数据添加到 Accces 中。（我不太会编程）

from tkinter import *
import pypyodbc
import ctypes

form=Tk ()
form.title ("Add data")
form.geometry ('400x200')

#Create connection
con = pypyodbc.connect('DRIVER={Microsoft Access Driver (*.mdb)};UID=admin;UserCommitSync=Yes;Threads=3;SafeTransactions=0;PageTimeout=5;MaxScanRows=8;MaxBufferSize=2048;FIL={MS Access};DriverId=25;DefaultDir=C:/Users/HP/Desktop/PITL;DBQ=C:/Users/HP/Desktop/PITL/PITL.mdb;')
cursor = con.cursor ()

a = Entry (form, width=20, font="Arial 16")
a.pack ()
b = Entry (form, width=20, font="Arial 16")
b.pack ()

def Add (event):
    cursor.execute ("INSERT INTO Crime (`Number_of_article`, `ID_of_criminal`) VALUES (?, ?)", (a, b))

con.commit ()
cursor.close ()
con.close ()

Button=Button(form, text = 'PUSH ME')
Button.pack ()
Button.bind ('<Button-1>', Add)

form.mainloop ()

我的错误是：

Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Users\HP\AppData\Local\Programs\Python\Python36-32\lib\tkinter\__init__.py", line 1699, in __call__
    return self.func(*args)
  File "C:\Users\HP\Desktop\PITL\ADD DATA.py", line 19, in Add
    cursor.execute ("INSERT INTO Crime (`Number_of_article`, `ID_of_criminal`) VALUES (?, ?)", (a, b))
  File "C:\Users\HP\AppData\Local\Programs\Python\Python36-32\lib\site-packages\pypyodbc-1.3.4-py3.6.egg\pypyodbc.py", line 1470, in execute
    self._free_stmt(SQL_CLOSE)
  File "C:\Users\HP\AppData\Local\Programs\Python\Python36-32\lib\site-packages\pypyodbc-1.3.4-py3.6.egg\pypyodbc.py", line 1987, in _free_stmt
    raise ProgrammingError('HY000','Attempt to use a closed connection.')
pypyodbc.ProgrammingError: ('HY000', 'Attempt to use a closed connection.')

此外，如果我将此代码（下方）更改为 a = '*any number*' b = '*any number*'，程序将运行

a = Entry (form, width=20, font="Arial 16")
a.pack ()
b = Entry (form, width=20, font="Arial 16")
b.pack ()

Answer 1

您要在调用 Add 之前关闭连接，将关闭调用移至代码底部。

Answer 2

.close() 语句的一般最佳做法是将它们放在代码的末尾。但这在这种情况下可能会产生错误。现在尝试删除 .close() 语句。

from tkinter import *
import pypyodbc
import ctypes

form=Tk ()
form.title ("Add data")
form.geometry ('400x200')

#Create connection
con = pypyodbc.connect('DRIVER={Microsoft Access Driver(*.mdb)};UID=admin;UserCommitSync=Yes;Threads=3;SafeTransactions=0;PageTimeout=5;    MaxScanRows=8;MaxBufferSize=2048;FIL={MS Access};DriverId=25;DefaultDir=C:/Users/HP/Desktop/PITL;DBQ=C:/Users/HP/Desktop/PITL/PITL.mdb;')
cursor = con.cursor ()

a = Entry (form, width=20, font="Arial 16")
a.pack ()
b = Entry (form, width=20, font="Arial 16")
b.pack ()

def Add (event):
    cursor.execute ("INSERT INTO Crime (`Number_of_article`, `ID_of_criminal`) VALUES (?, ?)", (a, b))


Button=Button(form, text = 'PUSH ME')
Button.pack ()
Button.bind ('<Button-1>', Add)

form.mainloop ()

con.commit ()

我有错误 'Attempt to use a closed connection.'

I have error 'Attempt to use a closed connection.'

python

ms-access

tkinter

pypyodbc