反复摸索终于搞定
Dim dlg As New OpenFileDialog '定义一个新的OpenFileDialog
dlg.InitialDirectory="D:\My Documents\退耕报表" '最初显示的目录
dlg.Filter= "Excel文件|*.xls|Word文件|*.doc|Access文件|*.mdb" '设置筛选器
dlg.MultiSelect = True '选择多个文件
If dlg.ShowDialog = DialogResult.OK Then '如果用户单击了确定按钮
For Each fl As String In dlg.FileNames
Dim App As New MSExcel.Application
Dim Wb As MSExcel.Workbook = App.WorkBooks.Open(""& fl & "")
Dim Wd As MSExcel.Window = Wb.Windows(1) '表示当前工作簿窗口
Dim Ws As MSExcel.WorkSheet = Wb.WorkSheets(1)
App.Visible = True
Next
End If