看看这个,绝对正确:
Private Sub Toolbar_Option_ButtonClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Toolbar_Option.ButtonClick
Dim btn As ToolbarButton = sender
Dim SelectToolbar1BtnIndex As String
SelectToolbar1BtnIndex = Toolbar_Option.Items.FlatIndexOf(btn).ToString()
Select Case SelectToolbar1BtnIndex
Case "0"
MultiPage_SetPage.SelectedIndex = 0
Case "2"
MultiPage_SetPage.SelectedIndex = 1
Case "4"
MultiPage_SetPage.SelectedIndex = 2
Case Else
MultiPage_SetPage.SelectedIndex = 0
End Select
End Sub