vb6-Operating Database

Usually do the database operation more want to put the content of often use together, I also lazy, in a book of engineering examples picked a bas, fix change, do this use it.

1  PublicStrcnn as String  'Database connection String2  PublicAdocnn asADODB. Connection'Database Connection3  PublicIsconnect as Boolean  'determine if the connection4 5 6 Private SubConnect ()'connecting to a database7      on Error GoToERR:8     IfIsconnect =True  Then  'returns if the connection is marked as true. Otherwise, it will go wrong9         Exit SubTen     End If One      A     SetADOCNN =NewADODB. Connection'key new to create new objects CNN -      withadocnn -. ConnectionString =strcnn the. ConnectionTimeout =Ten -         . Open -     End  with -Isconnect =True  'Set the connection token to indicate that you are connected to the database +     Exit Sub - ERR: +     IfERR =-2147467259  Then A         SetCnn = Nothing at         MsgBoxErr.Description &"Please check the database configuration!", vbOKOnly + vbinformation,"Connect" -     Else -         MsgBoxErr.Description &"Please check the database configuration!", vbexclamation,"Connect" -     End If -      - End Sub in  -  Public SubDisconnect ()'disconnecting from the database to     DimRc as Long +     IfIsconnect =False  Then Exit Sub 'If the connection is marked as false, indicating that the connection has been disconnected, return directly -Adocnn.close'Close Connection the      *     SetADOCNN = Nothing $Isconnect =FalsePanax Notoginseng End Sub -  the  Public SubDb_connect ()'using Connect_num to control database connections +Connect_num = Connect_num +1 A Connect the End Sub +  -  Public SubDb_disconnect () $     IfConnect_num >= Connect_loop_max Then $Connect_num =0 - Disconnect -     End If the End Sub - Wuyi  Public SubDbapi_disconnect ()'Force shutdown API-mode access to the database, counter reset theConnect_num =0 - Disconnect Wu End Sub -  About  Public SubExecsql (ByValTmpsql as String)'Execute database Operation statement $      on Error GoToERR: -     DimCmd as NewAdodb.command'create Command object cmd -Db_connect'connecting to a database -     SetCmd. ActiveConnection = adocnn'set the ActiveConnection property of CMD to specify the database connection with which it is associated ACmd.commandtext = Tmpsql'Set the command text to execute + cmd. Execute the     Setcmd = Nothing - Db_disconnect $     Exit Sub the ERR: the     MsgBoxErr.Description, -,"Execsql" the End Sub the  -  Public FunctionQuerysql (ByValTmpsql as String) asADODB. Recordset'Executing database query statements in      on Error GoToERR: the     DimRst as NewADODB. Recordset theDb_connect'connecting to a database About     IfIsconnect =False  Then Exit Function the     SetRst. ActiveConnection = adocnn'set the ActiveConnection property of the RST to specify the database connection to which it is associated theRst. CursorType =adOpenKeyset theRst. LockType = adLockOptimistic'Setting the lock type +Rst. Open Tmpsql'Open Record Set -     SetQuerysql = rst'back to record set the     Exit FunctionBayi ERR: the     MsgBoxErr.Description, -,"Querysql" the End Function -  -  Public FunctionGetFieldValue (Fieldvalue asVariant) as String theGetFieldValue =IIf( notIsNull (Fieldvalue), Fieldvalue,"") the End Function