Ibro

using System;

namespace SpanOfT_Dev
{
	public class Program
	{
		private static void Main(string[] args)
		{
			int[] arr = { 0, 1, 2, 3, 4, 5 };
			Span<int> span = arr.AsSpan();

Ibro

int[] arr = { 0, 1, 2, 3, 4, 5 };
Span<int> span = arr.AsSpan();

foreach (var number in span)
{
  Console.WriteLine(number);
}

Ibro

[HttpPost]
[ValidateAntiForgeryToken]
[AuthorizeResource(typeof(InsertCategoryRequirement))]
public async Task<IActionResult> Create([Bind("Id,Name,UserId")] Category category)
{
	ViewData["UserId"] = new SelectList(_context.Users, "Id", "Id", category.UserId);

	// If ModelState isn't valid, return to view immediately
	if (!ModelState.IsValid)
	{

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public class AuthorizeResourceAttribute : TypeFilterAttribute
	{
		public AuthorizeResourceAttribute(Type requirementType)
			: base(typeof(AuthorizeResourceFilter))
		{
			Arguments = new object[] { requirementType };
		}

		private class AuthorizeResourceFilter : IAsyncActionFilter
		{

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public class CategoriesController : Controller
{
	private readonly ApplicationDbContext _context;
	private readonly IAuthorizationService _authorizationService;

	public CategoriesController(ApplicationDbContext context, IAuthorizationService authorizationService)
	{
		_context = context;
		_authorizationService = authorizationService;
	}

Ibro

[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("Id,Name,UserId")] Category category)
{
	var authorizationResult = await _authorizationService.AuthorizeAsync(User, category, new InsertCategoryRequirement());
	if (!authorizationResult.Succeeded) // If user has no access show him 403
	{
		return new ForbidResult();
	}
	

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public class InsertCategoryHandler : AuthorizationHandler<InsertCategoryRequirement, Category>, IAuthorizationRequirement
{
	private readonly ISecurityService _securityService;

	public InsertCategoryHandler(ISecurityService securityService) => _securityService = securityService;

	protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context,
		InsertCategoryRequirement requirement, Category category)
	{

Ibro

[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("Id,Name,UserId")] Category category)
{
	ViewData["UserId"] = new SelectList(_context.Users, "Id", "Id", category.UserId);

	// If ModelState isn't valid, return to view immediately
	if (!ModelState.IsValid)
	{
		return View(category);

Ibro

[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("Id,Name,UserId")] Category category)
{
	// Populate UserId select list.
	ViewData["UserId"] = new SelectList(_context.Users, "Id", "Id", category.UserId);

	// If ModelState isn't valid, return to view immediately
	if (!ModelState.IsValid)
	{

Ibro

public class ApplicationDbContext : IdentityDbContext<ApplicationUser, ApplicationRole, string>
{
	public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
		: base(options)
	{
	}

	public DbSet<Category> Categories { get; set; }	
}