Dim lx As String = "Access 2000/2003" \'数据库类型
Dim value1, name1 As String
Dim dlg As New OpenFileDialog \'定义一个新的OpenFileDialog
dlg.Filter = "青橙接口文件|*.zjk" \'设置筛选器
dlg.InitialDirectory = ProjectPath & "数据库\\"
If dlg.ShowDialog = DialogResult.Ok Then \'如果用户单击了确定按钮
    name1 = dlg.FileName\'数据库名称
    Dim sjy As String = Rand.NextString(16) \'随机生成，避免重复
    Connections.Add(sjy, "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & name1 & ";Persist Security Info=False")
    If lst.Contains("A1_qdk") Then
        
       \'可以进一步判断，列名等是否与当前表一致
        
        For Each frm As WinForm.Form In forms \'关闭主窗口以外的所有窗口,确保没有其他窗口打开
            If frm.Name <> "主窗口" And frm.Opened Then
                frm.close()
            End If
        Next 
      
       
        value1 = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & name1 & ";Persist Security Info=False"
        
        Dim s As String = ""
        \'遍历当前属于此数据源的表
        For Each dt As DataTable In DataTables
            If dt.C Then
                s += "|" & dt.name
            End If
        Next
        s = s.Trim("|")
        
        \'卸载表
        DataTables.Unload(s)
        If Connections.Contains("青橙") Then
            Connections.Delete("青橙")
        End If
        
        
        Connections.add("青橙", value1) 
        DataTables.load(s) 
        
        \'  Application.Restart()            \'系统重新启动    
        MainTable = Tables("A1_qdk")
    End If 
End If

    \'遍历当前属于此数据源的表
    For Each dt As DataTable In DataTables
        If dt.C Then
            s += "|" & dt.name
        End If
    Next