Can't update image in ASP.NET Core MVC - asp.net-core

Question

I'm beginner to ASP.NET Core, I am trying to update an image in a database, I have some doubts about my code, image added to database but cannot update
AdminController
public async Task<ViewResult> Edit(int productId)
{
return View(await _repository.Products
.FirstOrDefaultAsync(p => p.ProductID == productId));
}
[HttpPost]
public async Task<IActionResult> Edit(Product product, IFormFile image)
{
if (ModelState.IsValid)
{
if(image != null && image.Length > 0)
{
var fileName = Path.GetFileName(image.FileName);
var filePath = Path.Combine(Directory.GetCurrentDirectory(), "wwwroot\\images\\items", fileName);
using(var fileSteam = new FileStream(filePath, FileMode.Create))
{
await image.CopyToAsync(fileSteam);
}
product.Image = fileName;
}
_repository.SaveProduct(product);
TempData["message"] = $"{product.Name} has been edit";
return RedirectToAction("Index");
}
else
{
return View(product);
}
}
Edit.cshtml
<form asp-action="Edit" method="post" enctype="multipart/form-data">
<input type="hidden" asp-for="ProductID" />
<div class="form-group">
<h4><label asp-for="Image"></label></h4>
<input asp-for="Image" type="file" class="form-control" />
</div>

Answer 1

I'm found where I was wrong, thanks Xing Zou! I updated the SaveProduct(product)
public Product SaveProduct(Product productDataUpdate)
{
var prod = _context.Products.Attach(productDataUpdate);
prod.State = Microsoft.EntityFrameworkCore.EntityState.Modified;
_context.SaveChanges();
return productDataUpdate;
}