public void ConfigureServices(IServiceCollection services)
{ 
    services.AddFeatureManagement().AddFeatureFilter<TimeWindowFilter>();
}

[FilterAlias("BrowserFilter")]
public class BrowserFilter:IFeatureFilter
    {
        private readonly IHttpContextAccessor _httpContextAccessor;

        public BrowserFilter(IHttpContextAccessor httpContextAccessor)
        {
            _httpContextAccessor = httpContextAccessor ?? throw new ArgumentNullException(nameof(httpContextAccessor));
        }

        public Task<bool> EvaluateAsync(FeatureFilterEvaluationContext context)
        {
            var userAgent = _httpContextAccessor.HttpContext.Request.Headers["User-Agent"].ToString();
            var settings = context.Parameters.Get<BrowserFilterSettings>();
            return Task.FromResult(settings.AllowedBrowsers.Any(userAgent.Contains));
        }
    }

using System.Threading.Tasks;

namespace Async05
{
    class Program
    {
        static void Main(string[] args)
        {
            var res = doSomethingAsync().Result;
        }

        static async Task<int> doSomethingAsync()
        {
            await Task.Delay(1);
            return 1;
        }
    }
}

using System;
using System.Collections.Generic;
using System.Net;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace Async05
{
    class Program
    {
        static void Main(string[] args)
        {
            var task = showTitlesAsync(new[]
            {
                "http://www.google.com",
                "https://www.dntips.ir"
            });
            task.Wait();

            Console.WriteLine();
            Console.WriteLine("Press any key to exit...");
            Console.ReadKey();
        }

        static async Task showTitlesAsync(IEnumerable<string> urls)
        {
            foreach (var url in urls)
            {
                var title = await getTitleAsync(url);
                Console.WriteLine(title);
            }
        }

        static async Task<string> getTitleAsync(string url)
        {
            var data = await new WebClient().DownloadStringTaskAsync(url);
            return getTitle(data);
        }

        private static string getTitle(string data)
        {
            const string patternTitle = @"(?s)<title>(.+?)</title>";
            var regex = new Regex(patternTitle);
            var mc = regex.Match(data);
            return mc.Groups.Count == 2 ? mc.Groups[1].Value.Trim() : string.Empty;
        }
    }
}

        static async Task showTitlesAsync(IEnumerable<string> urls)
        {
            foreach (var url in urls)
            {
                try
                {
                    var title = await getTitleAsync(url);
                    Console.WriteLine(title);
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex);
                }
            }
        }

 System.Net.WebException: The remote server returned an error: (502) Bad Gateway.
System.Net.WebException: The remote server returned an error: (502) Bad Gateway.

Press any key to exit...

public async Task<double> GetSum2Async()
        {
            try
            {
                var task1 = GetNumberAsync();
                var task2 = GetNumberAsync();

                var compositeTask = Task.WhenAll(task1, task2);
                await compositeTask.ContinueWith(x => { });

                return compositeTask.Result[0] + compositeTask.Result[1];
            }
            catch (Exception ex)
            {
                //todo: log ex
                throw;
            }
        }

        public async Task<double> GetSumAsync()
        {
            var leftOperand = await GetNumberAsync();
            var rightOperand = await GetNumberAsync();

            return leftOperand + rightOperand;
        }

using System;
using System.Threading.Tasks;

namespace Async01
{
    class Program
    {
        static void Main(string[] args)
        {
            Test2();
            Test();
            Console.ReadLine();

            GC.Collect();
            GC.WaitForPendingFinalizers();

            Console.ReadLine();
        }

        public static async Task Test()
        {
            throw new Exception();
        }

        public static async void Test2()
        {
            throw new Exception();
        }
    }
}

 Warning  1  Because this call is not awaited, execution of the current method continues before the call is completed.
Consider applying the 'await' operator to the result of the call.

using System;
using System.Threading.Tasks;

namespace Async01
{
    class Program
    {
        static void Main(string[] args)
        {
            TaskScheduler.UnobservedTaskException += TaskScheduler_UnobservedTaskException;

            //Test2();
            Test();
            Console.ReadLine();

            GC.Collect();
            GC.WaitForPendingFinalizers();

            Console.ReadLine();
        }

        private static void TaskScheduler_UnobservedTaskException(object sender, UnobservedTaskExceptionEventArgs e)
        {
            e.SetObserved();
            Console.WriteLine(e.Exception);
        }

        public static async Task Test()
        {
            throw new Exception();
        }

        public static async void Test2()
        {
            throw new Exception();
        }
    }
}

Task.Factory.StartNew(() => { throw new Exception(); });

Thread.Sleep(100);
GC.Collect();
GC.WaitForPendingFinalizers();

 <configuration>
    <runtime>
      <ThrowUnobservedTaskExceptions enabled="true"/>
    </runtime>
</configuration>

protected override void LoadState(Object navigationParameter, Dictionary<String, Object> pageState)
{
    try
    {
        ClickMeButton.Tapped += async (sender, args) =>
        {
             throw new Exception();        

        };
    }
    catch (Exception ex)
    {
        // This won’t catch exceptions!
        TextBlock1.Text = ex.Message;
    }
}

 public delegate void TappedEventHandler(object sender, TappedRoutedEventArgs e);

    public struct Maybe<T> : IEquatable<Maybe<T>>
        where T : class
    {
        private readonly T _value;

        private Maybe(T value)
        {
            _value = value;
        }

        public bool HasValue => _value != null;
        public T Value => _value ?? throw new InvalidOperationException();
        public static Maybe<T> None => new Maybe<T>();


        public static implicit operator Maybe<T>(T value)
        {
            return new Maybe<T>(value);
        }

        public static bool operator ==(Maybe<T> maybe, T value)
        {
            return maybe.HasValue && maybe.Value.Equals(value);
        }

        public static bool operator !=(Maybe<T> maybe, T value)
        {
            return !(maybe == value);
        }

        public static bool operator ==(Maybe<T> left, Maybe<T> right)
        {
            return left.Equals(right);
        }

        public static bool operator !=(Maybe<T> left, Maybe<T> right)
        {
            return !(left == right);
        }

        /// <inheritdoc />
        /// <summary>
        ///     Avoid boxing and Give type safety
        /// </summary>
        /// <param name="other"></param>
        /// <returns></returns>
        public bool Equals(Maybe<T> other)
        {
            if (!HasValue && !other.HasValue)
                return true;

            if (!HasValue || !other.HasValue)
                return false;

            return _value.Equals(other.Value);
        }

        /// <summary>
        ///     Avoid reflection
        /// </summary>
        /// <param name="obj"></param>
        /// <returns></returns>
        public override bool Equals(object obj)
        {
            if (obj is T typed)
            {
                obj = new Maybe<T>(typed);
            }

            if (!(obj is Maybe<T> other)) return false;

            return Equals(other);
        }

        /// <summary>
        ///     Good practice when overriding Equals method.
        ///     If x.Equals(y) then we must have x.GetHashCode()==y.GetHashCode()
        /// </summary>
        /// <returns></returns>
        public override int GetHashCode()
        {
            return HasValue ? _value.GetHashCode() : 0;
        }

        public override string ToString()
        {
            return HasValue ? _value.ToString() : "NO VALUE";
        }
    }

<Project Sdk="Microsoft.NET.Sdk.Web">
  <ItemGroup>
    <PackageReference Include="Parbad.AspNetCore" Version="1.1.0" />
    <PackageReference Include="Parbad.Storage.EntityFrameworkCore" Version="1.2.0" />
  </ItemGroup>
</Project>

<Project Sdk="Microsoft.NET.Sdk.Web">
  <ItemGroup>
    <PackageReference Include="Parbad.Storage.EntityFrameworkCore" Version="1.2.0" />
  </ItemGroup>
</Project>

namespace BlazorWasm.WebApi
{
    public class Startup
    {
        // ...

        public void ConfigureServices(IServiceCollection services)
        {
           // ...

            var connectionString = Configuration.GetConnectionString("DefaultConnection");

            services.AddParbad()
                    .ConfigureHttpContext(httpContextBuilder => httpContextBuilder.UseDefaultAspNetCore())
                    .ConfigureGateways(gatewayBuilder =>
                    {
                        gatewayBuilder
                            .AddParbadVirtual()
                            .WithOptions(gatewayOptions => gatewayOptions.GatewayPath = "/MyVirtualGateway");
                    })
                    .ConfigureStorage(storageBuilder =>
                    {
                        storageBuilder.UseEfCore(efCoreOptions =>
                            {
                                var assemblyName = typeof(ApplicationDbContext).Assembly.GetName().Name;
                                efCoreOptions.ConfigureDbContext = db =>
                                    db.UseSqlServer(
                                        connectionString,
                                        sqlServerOptionsAction: sqlOptions => sqlOptions.MigrationsAssembly(assemblyName)
                                    );
                            });
                    })
                    .ConfigureAutoTrackingNumber(opt => opt.MinimumValue = 1)
                    .ConfigureOptions(parbadOptions =>
                    {
                        // parbadOptions.Messages.PaymentSucceed = "YOUR MESSAGE";
                    });

           // ...
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
           // ...

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });

            if (env.IsDevelopment())
            {
                app.UseParbadVirtualGatewayWhenDeveloping();
            }
            else
            {
                app.UseParbadVirtualGateway();
            }
        }
    }
}

using System;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace BlazorServer.Entities
{
    public class RoomOrderDetail
    {
        // ...

        [Required]
        public long ParbadTrackingNumber { get; set; }

        public bool IsPaymentSuccessful { get; set; }

        public string Status { get; set; }
    }
}

dotnet tool update --global dotnet-ef --version 5.0.4
dotnet build

dotnet ef migrations --startup-project ../../BlazorWasm/BlazorWasm.WebApi/ add AddParbadFields --context ApplicationDbContext
dotnet ef migrations --startup-project ../../BlazorWasm/BlazorWasm.WebApi/ add AddParbad --context Parbad.Storage.EntityFrameworkCore.Context.ParbadDataContext

dotnet ef --startup-project ../../BlazorWasm/BlazorWasm.WebApi/ database update --context ApplicationDbContext
dotnet ef --startup-project ../../BlazorWasm/BlazorWasm.WebApi/ database update --context Parbad.Storage.EntityFrameworkCore.Context.ParbadDataContext

https://localhost:5001/api/ParbadPayment/PayRoomOrder?orderId=1&amount=1000

https://localhost:5002/payment-result/OrderId/TrackingNumber/Message

https://localhost:5001/api/ParbadPayment/PayRoomOrder?orderId=1&amount=1000

namespace BlazorWasm.WebApi.Controllers
{
    [Route("api/[controller]/[action]")]
    [ApiController]
    public class ParbadPaymentController : Controller
    {
        private readonly IConfiguration _configuration;
        private readonly IOnlinePayment _onlinePayment;
        private readonly IRoomOrderDetailsService _roomOrderService;

        public ParbadPaymentController(
            IConfiguration configuration,
            IOnlinePayment onlinePayment,
            IRoomOrderDetailsService roomOrderService)
        {
            _configuration = configuration;
            _onlinePayment = onlinePayment ?? throw new ArgumentNullException(nameof(onlinePayment));
            _roomOrderService = roomOrderService ?? throw new ArgumentNullException(nameof(roomOrderService));
        }

        [HttpGet]
        public async Task<IActionResult> PayRoomOrder(int orderId, long amount)
        {
            var verifyUrl = Url.Action(
                    action: nameof(ParbadPaymentController.VerifyRoomOrderPayment),
                    controller: nameof(ParbadPaymentController).Replace("Controller", string.Empty),
                    values: null, protocol: Request.Scheme);

            var result = await _onlinePayment.RequestAsync(invoiceBuilder =>
                invoiceBuilder.UseAutoIncrementTrackingNumber()
                            .SetAmount(amount)
                            .SetCallbackUrl(verifyUrl)
                            .UseParbadVirtual()
            );

            if (result.IsSucceed)
            {
                await _roomOrderService.UpdateRoomOrderTrackingNumberAsync(orderId, result.TrackingNumber);

                // It will redirect the client to the gateway.
                return result.GatewayTransporter.TransportToGateway();
            }
            else
            {
                return Redirect(getClientReturnUrl(orderId, result.TrackingNumber, result.Message));
            }
        }

        [HttpGet, HttpPost]
        public async Task<IActionResult> VerifyRoomOrderPayment()
        {
            var invoice = await _onlinePayment.FetchAsync();
            var orderDetail = await _roomOrderService.GetOrderDetailByTrackingNumberAsync(invoice.TrackingNumber);
            if (invoice.Status == PaymentFetchResultStatus.AlreadyProcessed)
            {
                return Redirect(getClientReturnUrl(orderDetail.Id, invoice.TrackingNumber, "The payment is already processed."));
            }

            var verifyResult = await _onlinePayment.VerifyAsync(invoice);
            if (verifyResult.Status == PaymentVerifyResultStatus.Succeed)
            {
                var result = await _roomOrderService.MarkPaymentSuccessfulAsync(verifyResult.TrackingNumber, verifyResult.Amount);
                if (result == null)
                {
                    return Redirect(getClientReturnUrl(orderDetail.Id, verifyResult.TrackingNumber, "Can not mark payment as successful"));
                }
                return Redirect(getClientReturnUrl(orderDetail.Id, verifyResult.TrackingNumber, verifyResult.Message));
            }
            return Redirect(getClientReturnUrl(orderDetail.Id, verifyResult.TrackingNumber, verifyResult.Message));
        }

        private string getClientReturnUrl(int orderId, long trackingNumber, string errorMessage)
        {
            var clientBaseUrl = _configuration.GetValue<string>("Client_URL");
            return new Uri(new Uri(clientBaseUrl),
                $"/payment-result/{orderId}/{trackingNumber}/{WebUtility.UrlEncode(errorMessage)}").ToString();
        }
    }
}

[HttpGet]
public async Task<IActionResult> PayRoomOrder(int orderId, long amount)

namespace BlazorServer.Services
{
    public class RoomOrderDetailsService : IRoomOrderDetailsService
    {
        // ...

        public async Task UpdateRoomOrderTrackingNumberAsync(int roomOrderId, long trackingNumber)
        {
            var order = await _dbContext.RoomOrderDetails.FindAsync(roomOrderId);
            if (order == null)
            {
                return;
            }

            order.ParbadTrackingNumber = trackingNumber;
            _dbContext.RoomOrderDetails.Update(order);
            await _dbContext.SaveChangesAsync();
        }
    }
}

[HttpGet, HttpPost]
public async Task<IActionResult> VerifyRoomOrderPayment()

namespace BlazorServer.Services
{
    public class RoomOrderDetailsService : IRoomOrderDetailsService
    {
        // ...

        public async Task<RoomOrderDetailsDTO> GetOrderDetailByTrackingNumberAsync(long trackingNumber)
        {
            var roomOrderDetailsDTO = await _dbContext.RoomOrderDetails
                                            .Include(u => u.HotelRoom)
                                                .ThenInclude(x => x.HotelRoomImages)
                                            .ProjectTo<RoomOrderDetailsDTO>(_mapperConfiguration)
                                            .FirstOrDefaultAsync(u => u.ParbadTrackingNumber == trackingNumber);

            roomOrderDetailsDTO.HotelRoomDTO.TotalDays =
                roomOrderDetailsDTO.CheckOutDate.Subtract(roomOrderDetailsDTO.CheckInDate).Days;
            return roomOrderDetailsDTO;
        }
    }
}

namespace BlazorServer.Services
{
    public class RoomOrderDetailsService : IRoomOrderDetailsService
    {
        // ...

        public async Task<RoomOrderDetailsDTO> MarkPaymentSuccessfulAsync(long trackingNumber, long amount)
        {
            var order = await _dbContext.RoomOrderDetails.FirstOrDefaultAsync(x => x.ParbadTrackingNumber == trackingNumber);
            if (order?.IsPaymentSuccessful != false || order.TotalCost != amount)
            {
                return null;
            }

            order.IsPaymentSuccessful = true;
            order.Status = BookingStatus.Booked;
            var markPaymentSuccessful = _dbContext.RoomOrderDetails.Update(order);
            await _dbContext.SaveChangesAsync();
            return _mapper.Map<RoomOrderDetailsDTO>(markPaymentSuccessful.Entity);
        }
    }
}

        private string getClientReturnUrl(int orderId, long trackingNumber, string errorMessage)
        {
            var clientBaseUrl = _configuration.GetValue<string>("Client_URL");
            return new Uri(new Uri(clientBaseUrl),
                $"/payment-result/{orderId}/{trackingNumber}/{WebUtility.UrlEncode(errorMessage)}").ToString();
        }

{
   "Client_URL": "https://localhost:5002/"
}

@page "/hotel-room-details/{Id:int}"

@inject IJSRuntime JsRuntime
@inject ILocalStorageService LocalStorage
@inject IClientHotelRoomService HotelRoomService
@inject IClientRoomOrderDetailsService RoomOrderDetailsService
@inject NavigationManager NavigationManager
@inject HttpClient HttpClient

// ...

@code {

    // ...

    private async Task HandleCheckout()
    {
        if (!await HandleValidation())
        {
            return;
        }

        try
        {
            HotelBooking.OrderDetails.ParbadTrackingNumber = -1;
            HotelBooking.OrderDetails.RoomId = HotelBooking.OrderDetails.HotelRoomDTO.Id;
            HotelBooking.OrderDetails.TotalCost = HotelBooking.OrderDetails.HotelRoomDTO.TotalAmount;
            var roomOrderDetailsSaved = await RoomOrderDetailsService.SaveRoomOrderDetailsAsync(HotelBooking.OrderDetails);

            await LocalStorage.SetItemAsync(ConstantKeys.LocalRoomOrderDetails, roomOrderDetailsSaved);

            var paymentUri = new UriBuilderExt(new Uri(HttpClient.BaseAddress, $"/api/ParbadPayment/PayRoomOrder"))
                            .AddParameter("orderId", roomOrderDetailsSaved.Id.ToString())
                            .AddParameter("amount", roomOrderDetailsSaved.TotalCost.ToString())
                            .Uri;
            NavigationManager.NavigateTo(paymentUri.ToString(), forceLoad: true);
        }
        catch (Exception e)
        {
            await JsRuntime.ToastrError(e.Message);
        }
    }

    // ...
}

namespace BlazorWasm.WebApi.Controllers
{
    [ApiController]
    [Route("api/[controller]/[action]")]
    public class RoomOrderController : Controller
    {
        private readonly IRoomOrderDetailsService _roomOrderService;

        public RoomOrderController(IRoomOrderDetailsService roomOrderService)
        {
            _roomOrderService = roomOrderService ?? throw new ArgumentNullException(nameof(roomOrderService));
        }

        [HttpPost]
        public async Task<IActionResult> Create([FromBody] RoomOrderDetailsDTO details)
        {
            var result = await _roomOrderService.CreateAsync(details);
            return Ok(result);
        }

        [HttpGet]
        public async Task<IActionResult> GetOrderDetail(int trackingNumber)
        {
            var result = await _roomOrderService.GetOrderDetailByTrackingNumberAsync(trackingNumber);
            return Ok(result);
        }
    }
}

namespace BlazorServer.Services
{
    public class RoomOrderDetailsService : IRoomOrderDetailsService
    {
        // ...

        public async Task<RoomOrderDetailsDTO> CreateAsync(RoomOrderDetailsDTO details)
        {
            var roomOrder = _mapper.Map<RoomOrderDetail>(details);
            roomOrder.Status = BookingStatus.Pending;
            var result = await _dbContext.RoomOrderDetails.AddAsync(roomOrder);
            await _dbContext.SaveChangesAsync();
            return _mapper.Map<RoomOrderDetailsDTO>(result.Entity);
        }


        public async Task<RoomOrderDetailsDTO> GetOrderDetailByTrackingNumberAsync(long trackingNumber)
        {
            var roomOrderDetailsDTO = await _dbContext.RoomOrderDetails
                                            .Include(u => u.HotelRoom)
                                                .ThenInclude(x => x.HotelRoomImages)
                                            .ProjectTo<RoomOrderDetailsDTO>(_mapperConfiguration)
                                            .FirstOrDefaultAsync(u => u.ParbadTrackingNumber == trackingNumber);

            roomOrderDetailsDTO.HotelRoomDTO.TotalDays =
                roomOrderDetailsDTO.CheckOutDate.Subtract(roomOrderDetailsDTO.CheckInDate).Days;
            return roomOrderDetailsDTO;
        }

       // ...
    }
}

namespace BlazorWasm.Client.Services
{
    public interface IClientRoomOrderDetailsService
    {
        Task<RoomOrderDetailsDTO> SaveRoomOrderDetailsAsync(RoomOrderDetailsDTO details);
        Task<RoomOrderDetailsDTO> GetOrderDetailAsync(long trackingNumber);
    }
}

namespace BlazorWasm.Client.Services
{
    public class ClientRoomOrderDetailsService : IClientRoomOrderDetailsService
    {
        private readonly HttpClient _httpClient;

        public ClientRoomOrderDetailsService(HttpClient httpClient)
        {
            _httpClient = httpClient ?? throw new ArgumentNullException(nameof(httpClient));
        }

        public Task<RoomOrderDetailsDTO> GetOrderDetailAsync(long trackingNumber)
        {
            // How to url-encode query-string parameters properly
            var uri = new UriBuilderExt(new Uri(_httpClient.BaseAddress, $"/api/roomorder/GetOrderDetail"))
                            .AddParameter("trackingNumber", trackingNumber.ToString())
                            .Uri;
            return _httpClient.GetFromJsonAsync<RoomOrderDetailsDTO>(uri);

        }

        public async Task<RoomOrderDetailsDTO> SaveRoomOrderDetailsAsync(RoomOrderDetailsDTO details)
        {
            details.UserId = "unknown user!";
            var response = await _httpClient.PostAsJsonAsync("api/roomorder/create", details);
            var responseContent = await response.Content.ReadAsStringAsync();
            if (response.IsSuccessStatusCode)
            {
                return JsonSerializer.Deserialize<RoomOrderDetailsDTO>(responseContent);
            }
            else
            {
                //var errorModel = JsonSerializer.Deserialize<ErrorModel>(responseContent);
                throw new InvalidOperationException(responseContent);
            }
        }
    }
}

namespace BlazorWasm.Client
{
    public class Program
    {
        public static async Task Main(string[] args)
        {
            // ...
            builder.Services.AddScoped<IClientRoomOrderDetailsService, ClientRoomOrderDetailsService>();

var paymentUri = new UriBuilderExt(new Uri(HttpClient.BaseAddress, $"/api/ParbadPayment/PayRoomOrder"))
    .AddParameter("orderId", roomOrderDetailsSaved.Id.ToString())
    .AddParameter("amount", roomOrderDetailsSaved.TotalCost.ToString())
    .Uri;
NavigationManager.NavigateTo(paymentUri.ToString(), forceLoad: true);

@page "/payment-result/{OrderId:int}/{TrackingNumber:long}/{Message}"
@inject ILocalStorageService LocalStorage
@inject IClientRoomOrderDetailsService RoomOrderDetailService
@inject IJSRuntime JsRuntime
@inject NavigationManager NavigationManager

@if (IsLoading)
{
    <div style="position:fixed;top:50%;left:50%;margin-top:-50px;margin-left:-100px;">
        <img src="images/ajax-loader.gif" />
    </div>
}
else
{
    <div class="container">
        <div class="row mt-4 pt-4">
            <div class="col-10 offset-1 text-center">
            @if(IsPaymentSuccessful)
            {
                <h2 class="text-success">Booking Confirmed!</h2>
                <p>Your room has been booked successfully with order id @OrderId & tracking number @TrackingNumber .</p>
            }
            else
            {
                <h2 class="text-warning">Booking Failed!</h2>
                <p>@Message</p>
            }
            <a class="btn btn-primary" href="hotel-rooms">Back to rooms</a>
            </div>
        </div>
    </div>
}

@code
{
    private bool IsLoading;
    private bool IsPaymentSuccessful;

    [Parameter] public int OrderId { set; get; }
    [Parameter] public long TrackingNumber { set; get; }
    [Parameter] public string Message { set; get; }

    protected override async Task OnInitializedAsync()
    {
        IsLoading = true;
        try
        {
            var finalOrderDetail = await RoomOrderDetailService.GetOrderDetailAsync(TrackingNumber);
            var localOrderDetail = await LocalStorage.GetItemAsync<RoomOrderDetailsDTO>(ConstantKeys.LocalRoomOrderDetails);
            if(finalOrderDetail is not null &&
                finalOrderDetail.IsPaymentSuccessful &&
                finalOrderDetail.Status == BookingStatus.Booked &&
                localOrderDetail is not null &&
                localOrderDetail.TotalCost == finalOrderDetail.TotalCost)
            {
                IsPaymentSuccessful = true;
                await LocalStorage.RemoveItemAsync(ConstantKeys.LocalRoomOrderDetails);
                await LocalStorage.RemoveItemAsync(ConstantKeys.LocalInitialBooking);
            }
            else
            {
                IsPaymentSuccessful = false;
            }
        }
        catch(Exception ex)
        {
            await JsRuntime.ToastrError(ex.Message);
        }
        finally
        {
            IsLoading = false;
        }
    }
}

@page "/payment-result/{OrderId:int}/{TrackingNumber:long}/{Message}"

    public class HotelRoomDTO
    {
        public bool IsBooked { get; set; }

        // ...
    }

namespace BlazorServer.Services
{
    public class HotelRoomService : IHotelRoomService
    {
       // ...

        public async Task<List<HotelRoomDTO>> GetAllHotelRoomsAsync(DateTime? checkInDateStr, DateTime? checkOutDatestr)
        {
            var hotelRooms = await _dbContext.HotelRooms
                        .Include(x => x.HotelRoomImages)
                        .Include(x => x.RoomOrderDetails)
                        .ProjectTo<HotelRoomDTO>(_mapperConfiguration)
                        .ToListAsync();

            foreach (var hotelRoom in hotelRooms)
            {
                hotelRoom.IsBooked = isRoomBooked(hotelRoom, checkInDateStr, checkOutDatestr);
            }

            return hotelRooms;
        }

        public async Task<HotelRoomDTO> GetHotelRoomAsync(int roomId, DateTime? checkInDate, DateTime? checkOutDate)
        {
            var hotelRoom = await _dbContext.HotelRooms
                            .Include(x => x.HotelRoomImages)
                            .Include(x => x.RoomOrderDetails)
                            .ProjectTo<HotelRoomDTO>(_mapperConfiguration)
                            .FirstOrDefaultAsync(x => x.Id == roomId);
            hotelRoom.IsBooked = isRoomBooked(hotelRoom, checkInDate, checkOutDate);
            return hotelRoom;
        }

        private bool isRoomBooked(HotelRoomDTO hotelRoom, DateTime? checkInDate, DateTime? checkOutDate)
        {
            if (checkInDate == null || checkOutDate == null)
            {
                return false;
            }

            return hotelRoom.RoomOrderDetails.Any(x => x.IsPaymentSuccessful &&
                        //check if checkin date that user wants does not fall in between any dates for room that is booked
                        ((checkInDate < x.CheckOutDate && checkInDate.Value.Date >= x.CheckInDate)
                        //check if checkout date that user wants does not fall in between any dates for room that is booked
                        || (checkOutDate.Value.Date > x.CheckInDate.Date && checkInDate.Value.Date <= x.CheckInDate.Date))
                    );
        }
    }
}

@if (room.IsBooked)
{
    <button disabled class="btn btn-secondary btn-block">Sold Out</button>
}
else
{
    <a href="@($"hotel-room-details/{room.Id}")" class="btn btn-success btn-block">Book</a>
}

@if (HotelBooking.OrderDetails.HotelRoomDTO.IsBooked)
{
    <button disabled class="btn btn-secondary btn-block">Sold Out</button>
}
else
{
    <button type="submit" class="btn btn-success form-control">Checkout Now</button>
}