How to return top previous URL after Edit in ASP.NET Core - asp.net-core-1.0

Question

I am using asp,net core and have used the tutorial to create sorted, paged and search page (Index). Once I edit an item from this page the controller always dumps me back to the default index page. How do I return to the previous URL. Many thanks.
Here is a section of my controller file.
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Edit(int id, Bind("id,UserPassword,user")] UserProfiles userProfiles)
{
var users = from u in _context.UserProfiles
select u;
if (id != userProfiles.id)
{
return NotFound();
}
if (ModelState.IsValid)
{
try
{
_context.Update(userProfiles);
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!UserProfilesExists(userProfiles.id))
{
return NotFound();
}
else
{
throw;
}
}
// ***************
// Redirect to the previous URL,i.e. the Index
return Redirect(TempData["PreviousURL"].ToString()) ;
}
return View(userProfiles);
}
public async Task<IActionResult> Index(string sortOrder, string currentFilter, string searchString, int? page)
{
ViewData["CurrentSort"] = sortOrder;
ViewData["NameSortParm"] = String.IsNullOrEmpty(sortOrder) ? "name_desc" : "";
// paging
if (searchString != null)
{
page = 1;
}
else
{
searchString = currentFilter;
}
// search
ViewData["CurrentFilter"] = searchString;
var users = from u in _context.UserProfiles
select u;
if (!String.IsNullOrEmpty(searchString))
{
users = users.Where(u => u.user.Contains(searchString)
);
}
//sort
switch (sortOrder)
{
case "name_desc":
users = users.OrderByDescending(u => u.user);
break;
default:
users = users.OrderBy(s => s.user);
break;
}
// ***************
// store the current path and query string in TempData["PreviousURL" session variable
TempData["PreviousURL"] = HttpContext.Request.Path.ToString() + HttpContext.Request.QueryString.ToString();
return View(await PaginatedList<UserProfiles>.CreateAsync(users.AsNoTracking(), page ?? 1, pageSize));
}
This is my first MVC project.

Answer 1

It depends on your logic where controller takes you after saving data.
You need to pass search, sort and paging related data to controller when saving data. You can send them as part of extra post data, as query string parameters or as part of the model itself which is being posted.
After saving data retrieve data based on those parameters and populater your view with that paged, filtred and sorted data.

Answer 2

I solved my problem with the use of session variables: ViewData, ViewBag and TempData. The following two pages were very useful:
https://www.codeproject.com/Articles/476967/What-is-ViewData-ViewBag-and-TempData-MVC-Option
http://andrewlock.net/an-introduction-to-session-storage-in-asp-net-core/
Please see edited question above for the solution.