Dropdownlist within DetailsView

[Madison]

Hi all,
I'm using DetailsView for my page. I have Dropdownlist in Templatefield for
EditItemTemplate and InsertItemTemplate. When users pick any item in
dropdownlist then I need to populate values for 5 textbox in detailsview. I
can do by using button with CommandName to populate values. I do not want the
users have to click on the button to populate. How can I populate the
textboxes after the users picked the item in the dropdownlist (dropDownList
SelectedIndexChanged)? I know I use SelectedIndexChanged if the dropdownlist
is not inside DetailsView.

Any ideas.

Thank you.