// GET: Admin/Cakes/Edit/5
public async Task <IActionResult> Edit(int?id)
{
if (id == null)
{
return(NotFound());
}
var cake = await context.Cakes.FindAsync(id);
if (cake == null)
{
return(NotFound());
}
var viewModel = new EditCakeViewModel
{
Id = cake.Id,
Name = cake.Name,
Description = cake.Description,
ImageUrl = cake.ImageUrl,
Price = cake.Price
};
// Retrieve categories for dropdown box
var categories = context.Categories.ToList()
.Select(c => new SelectListItem {
Value = c.Id.ToString(), Text = c.Name.ToString()
}).ToList();
ViewBag.Categories = categories;
return(View(viewModel));
}
public async Task <IActionResult> Edit(int id, EditCakeViewModel viewModel)
{
if (id != viewModel.Id)
{
return(NotFound());
}
if (ModelState.IsValid)
{
// Retrieve associated category (in case of unselection, category id will be set to default value "1")
string categoryIdString = Request.Form["Categories"];
bool categoryIdIsValid = int.TryParse(categoryIdString, out int categoryIdParsed);
int categoryId = categoryIdIsValid ? categoryIdParsed : 0;
var associatedCategory = await context.Categories.FindAsync(categoryId);
// Retrieve located cake and its categories
var locatedCake = await context.Cakes.Include(c => c.Categories).FirstOrDefaultAsync(c => c.Id == viewModel.Id);
var locatedCakeCategories = locatedCake.Categories.ToList();
locatedCake.Name = viewModel.Name;
locatedCake.Description = viewModel.Description;
locatedCake.ImageUrl = viewModel.ImageUrl;
locatedCake.Price = viewModel.Price;
// Context multiple tracking problem (context cannot track same ids simultaneously)
//var cake = new Cake(
// viewModel.Id,
// viewModel.Name,
// viewModel.Description,
// viewModel.ImageUrl,
// viewModel.Price
// );
if (associatedCategory != null &&
!locatedCakeCategories.Contains(associatedCategory))
{
locatedCake.Categories.Add(associatedCategory);
}
try
{
context.Update(locatedCake);
await context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!CakeExists(locatedCake.Id))
{
return(NotFound());
}
else
{
throw;
}
}
return(RedirectToAction(nameof(Index)));
}
return(View(viewModel));
}