send an alert to the user

Hi,

I have a button that would add partid to the list. what I want
is to send a user a javascript message saying that "the tire you selected
have been added to your cart".
before redirect them to other page.

here's what I have:

      protected void AddToCart_Command(object sender, CommandEventArgs e)
      {
            if (e.CommandName == "PostBack")
            {
                  var partIDs = Session["PartIDs"] as List<int>;
                  if (partIDs == null)
                        partIDs = new List<int>();
                  partIDs.Add(int.Parse(e.CommandArgument.ToString()));
                  Session["PartIDs"] = partIDs;
            }

        I need javascript message here = "The tires you selected have been added to your cart";

       Response.Redirect("tire-search-results.aspx?Brand=" + HDBrand.Value + "&SectionWidths=" + HDSectionWidths.Value +
                "&AspectRatios=" + HDAspectRatios.Value + "&Rims=" + HDRims.Value + "&TireSizeDiameter=" + HDTireSizeDiameter.Value +
                "&TireSizeSideWall=" + HDTireSizeSideWall.Value + "&TireSizeWidth=" + HDTireSizeWidth.Value +
                 "&Zip=" + HDZip.Value
                + "&Year=" + HDYear.Value + "&Make=" + HDMake.Value +
                "&Model=" + HDModel.Value + "&Option=" + HDOption.Value
           );

}