Question

我有两个名为frmChooseDBase和frmMain的表单。 frmChooseDBase用于选择文件（数据库文件）。完成选择数据库后，frmMain将加载从frmChooseDBase中选择的数据库。我怎么做dat？任何帮助。这是我的示例代码：

Public Class frmChooseDBase
    Public sr As String
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If OpenFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
            sr = OpenFileDialog1.FileName
            Me.Hide()
            FrmMain.Show()
        End If
    End Sub
End Class

Private Sub FrmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Desktop\'" & frmChooseDBase.sr & "';Extended Properties=Excel 8.0"
        con.Open()


 FillDGView("SELECT [CCCD Loading Database] AS [Transaction Date], [F2] AS [Unit Number], [F3] AS [Category], [F4] AS [Temp Required (C)], [F5] AS [Type Length], [F6] AS [T-State], [F7] AS [Position], [F8] AS [I/B Actual Visit], [F9] AS [Fright Kind] FROM [Loading$]")

    End Sub

Answer 1

如果您只想加载文件，则无需创建新表单。只需要一个按钮或菜单项，说明加载DB。单击它将弹出OpenFileDialog。将openFileDialog控件拖到窗体上，并为其指定一个有意义的名称（openFileDialog1 ...）

openFileDialog1.Title = "Please select a DB file"
openFileDialog1.InitialDirectory = "C:\"
openFileDialog1.Filter = "DB Files|*.extensionHERE"

If openFileDialog1.ShowDialog() = DialogResult.OK then
    'Do things here, the path is stored in openFileDialog1.Filename
    'If no files were selected, openFileDialog1.Filename is ""  
End If

如果您遇到困难或需要快速帮助，有很多使用openFileDialog控件的示例。

Answer 2

您甚至不必使用控件：

Dim ofd As OpenFileDialog = New OpenFileDialog
ofd.DefaultExt = "txt"
ofd.FileName = "defaultname"
ofd.InitialDirectory = "c:\"
ofd.Filter ="All files|*.*|Text files|*.txt"
ofd.Title = "Select file"
If ofd.ShowDialog() <> DialogResult.Cancel Then
    MsgBox(ofd.FileName)
End If

如何使用OpenFileDialog

2 个答案: