Forms Data Controls :: Restoring Gridview State After Going To A DetailsView To Edit?

I have a Gridview that is filtered by a DropDownList.

A sales rep can select all prospects or filter on the first letter of the company name.

They can also sort the complete list or filtered by sales rep name.

There are several reps in the list

It was requested that once the list is filtered by the first letter of the name

and sorted by the sales rep, that once they select a customer to edit in the DetailslView, and that

edit is completed by closing the detailsview, they return to the same sorted list. they return

to the same filtered list but the sort is back to the default which is the company name.

Here's what is in the code behind file.

protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
if (Session["selection"] != null)
{

[Code]....