主题：问题：窗口已经关闭，不能调用其中的控件

红色代码有问题，可以删除。

Dim dlg As new OpenFileDialog
dlg.Filter = "Excel文件|*.xls;*.xlsx"
If dlg.ShowDialog = DialogResult.OK Then
      If FileIsOpened( dlg.FileName )= True Then
          MessageBox.Show("请关闭文件后重新导入!")
          e.Form.Close
      Else
         If Connections.Contains("test") Then
             If DataTables.Contains("临时表") Then DataTables.Unload("临时表")
             Connections.Delete("test")
         Else
             e.Form.Close
         End If
         Connections.Add("test", "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & dlg.FileName & ";Extended Properties='Excel 8.0;HDR=yes'")
         Dim tns As String = ""
         For Each tn As String In Connections("test").GetTableNames
             tns &= tn & "|"
         Next
         e.Form.Controls("ComboBox1").ComboList = tns.TrimEnd("|")
         e.Form.Controls("ComboBox1").Selectedindex = 0
      End  If
Else
     e.Form.Close
End If