PRN222 - Chương 4: ASP.NET Core MVC

public IActionResult Save(Person person) {
  if (ModelState.IsValid) return Content("Valid");
  return Content("Error");
}

public class Person {
  public int Age { get; set; }
}
public IActionResult Save(Person person) {
  if (!ModelState.IsValid) {
    return Content("Invalid!");
  }
  return Content("OK");
}

public IActionResult Index() {
  ViewData["User"] = "Admin";
  return View();
}

public IActionResult Index() {
  ViewBag.Count = 10;
  return View();
}

services.AddScoped<IRepository, CustomerRepository>();

public IActionResult Index() {
  ViewData["Count"] = "10";
  return View();
}

// Controller
public IActionResult Index()
{
   ViewBag.Message = "Hello from ViewBag!";
   ViewData["Title"] = "My Page Title";
   return View();
}

// View
<p>@ViewBag.Message</p>
<h1>@ViewData["Title"]</h1>

// Controller
ViewData["Number"] = 123; // ViewData requires casting in the view.
ViewBag.Text = "Hello"; // ViewBag does not require casting.

//View
<p>Number: @((int)ViewData["Number"])</p>
<p>Text: @ViewBag.Text</p>