使用ADP进行mdb数据库开发的实现方案
优点：
1. 不依赖链接表
2. 纯粹使用ADO
3. 可轻松将mdb数据库应用升迁到SQLServer数据库应用
4. 可使用记录集作为报表的数据来源
5. 应用程序中无数据，数据安全容易得到保障
缺点：
1. 编程量相对较大
2. 开发不直观
实现原理：
1. ADO数据库连接的提供者一定是 “Microsoft.Access.OLEDB.10.0”，这样，记录集才能绑定到窗体和报表
2. ADO数据库连接的数据提供者是 “Microsoft.Jet.OLEDB.4.0” 或者 “Microsoft.ACE.OLEDB.12.0” 或者 “Microsoft.ACE.OLEDB.14.0”，即 mdb 数据库的提供者
3. 新建 ADP 时，取消数据库连接，即保证 ADP 处于断开状态， ADP 中无连接字符串。
对ADO进行了一次封装，作为全局的连接对象，放在 modADO 模块中
Option Compare Database
Option Explicit
' 作者：朱亦文(zhuyiwen)
' 时间：2013-07-11
Public Const DBFileName = "Data.mdb"
Public Const DBProvider = "Microsoft.Access.OLEDB.10.0"
Public Const DBDataProvider = "Microsoft.Jet.OLEDB.4.0"
Public Const DBPersistSecurityInfo = "False"
Public Const DBCursorLocation = adUseServer
Private m_Conn As ADODB.Connection
Private m_DBErrorNum As Integer
Private m_DBErrorMessage As String
Public Property Get DBErrorNumber() As Integer
DBErrorNumber = m_DBErrorNum
End Property
Public Property Get DBErrorMessage() As String
DBErrorMessage = m_DBErrorMessage
End Property
Public Property Get DBConnectionString() As String
DBConnectionString = _
"Provider=" & DBProvider & ";" & _
"Persist Security Info=" & DBPersistSecurityInfo & ";" & _
"Data Source=" & CurrentProject.Path & "\" & DBFileName & ";" & _
"Data Provider=" & DBDataProvider
End Property
Public Property Get DBConnection() As ADODB.Connection
On Error GoTo err_GetDBConnection
If m_Conn Is Nothing Then
Set m_Conn = New ADODB.Connection
m_Conn.CursorLocation = DBCursorLocation
End If
If m_Conn.State <> adStateOpen Then
m_Conn.Open DBConnectionString
End If
Set DBConnection = m_Conn
Exit Property
err_GetDBConnection:
m_DBErrorNum = Err.Number
m_DBErrorMessage = Err.Description
Err.Clear
End Property
Public Function DBClearError() As Boolean
m_DBErrorNum = 0
m_DBErrorMessage = ""
DBClearError = True
End Function
Public Function DBCloseConnection() As Boolean
On Error GoTo err_DBCloseConnection
If m_Conn Is Nothing Then
DBCloseConnection = True
End If
If m_Conn.State <> adStateClosed Then
m_Conn.Close
End If
Set m_Conn = Nothing
DBCloseConnection = True
Exit Function
err_DBCloseConnection:
m_DBErrorNum = Err.Number
m_DBErrorMessage = Err.Description
Err.Clear
End Function
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这样的好处，DBConnection 就相当于CurrentProject.Connection，便于程序移植。
附 件:
ADO报表示例下载
