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重新定位链接表二步走

栏目:access时间:2013-10-18 11:54:57

尽管Accxp网上有很多关于定位链接表的贴子,但还是有很多的朋友询问这方面的问题。应letter网友的提议,结合Alex总版主的重新定位链接表文件源码,现将这方面的具体操作介绍如下:

假设前台数据库文件名为frontBase.mdb
后台数据库文件名为backData.mdb
frontBase当中有链接表tbl1, tbl2, tbl3, …,链接到backData.mdb中

首先我们要在前台数据库文件的启动窗体加载事件中判断链接是否正确

方法是打开任意一个链接表,假设为tbl1,代码如下:

Public Function CheckLinks() As Boolean
' 检查到后台数据库的链接;如果链接存在且正确的话,返回 True 。  
   Dim dbs As Database, rst As DAO.Recordset  
   Set dbs = CurrentDb()
   ' 打开链接表查看表链接信息是否正确。
   On Error Resume Next
   Set rst = dbs.OpenRecordset(“tbl1”)
   rst.Close
   ' 如果没有错误,返回 True 。
   If Err = 0 Then
     CheckLinks = True
   Else
     CheckLinks = False
   End If  
End Function

启动窗体的加载事件:
Private Sub FORM_Load()
If CheckLinks = False then
Docmd.OpenFORM “frmConnect”
End If
End Sub

frmConnect 连接窗体如下图

[img]f:m.bmp[/img]


接下来的事情就是如何刷新链接表了。
上面的窗体右边的按钮是用用来调用API打开文件对话框,具体代码如下:
Declare Function GetOpenFileName Lib "comdlg32.dll" Alias "GetOpenFileNameA" (pOpenfilename As OPENFILENAME) As Boolean

Type OPENFILENAME
   lStructSize As Long
   hwndOwner As Long
   hInstance As Long
   lpstrFilter As String
   lpstrCustomFilter As String
   nMaxCustFilter As Long
   nFilterIndex As Long
   lpstrFile As String
   nMaxFile As Long
   lpstrFileTitle As String
   nMaxFileTitle As Long
   lpstrInitialDir As String
   lpstrTitle As String
   flags As Long
   nFileOffset As Integer
   nFileExtension As Integer
   lpstrDefExt As String
   lCustData As Long
   lpfnHook As Long
   lpTemplateName As String
End Type

Private Sub FileOpen_Click()
  Dim ofn As OPENFILENAME
  Dim rtn As String

  ofn.lStructSize = Len(ofn)
  ofn.hwndOwner = Me.hwnd

  ofn.lpstrFilter = "数据库文件 (*.mdb)" & VBNullChar & "*.mdb"
  ofn.lpstrFile = Space(254)
  ofn.nMaxFile = 255
  ofn.lpstrFileTitle = Space(254)
  ofn.nMaxFileTitle = 255
  ofn.lpstrInitialDir = CurrentProject.Path
  ofn.lpstrTitle = "后台数据文件为"
  ofn.flags = 6148

  rtn = GetOpenFileName(ofn)

  FileName.SetFocus
  If rtn = True Then
    FileName.Text = ofn.lpstrFile
    FileName.Text = FileName.Text
    OK.Enabled = True
  Else
    FileName.Text = ""
  End If
End Sub

连接按钮刷新链接表 ,代码如下:
Private Sub OK_Click()
Dim tabDef As TableDef
For Each tabDef In CurrentDb.TableDefs
If Len(tabDef.Connect) > 0 Then
tabDef.Connect = ";DATABASE=" & Me.FileName.Text & ";PWD=" + 后台数据库密码
tabDef.RefreshLink
End If
Next
MsgBox "连接成功!"
DoCmd.Close acFORM, Me.Name
End Sub


其实很简单只有两步,判断链接是否正确和刷新链接表。

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