重新定位链接表二步走

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)" & NullChar & "*.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。