Blazor Component Lifecycle

@page "/demo-books" @using System.Net.Http.Json @inject HttpClient Http <h3>Book List</h3> @if (isLoading) { <p>Loading books...</p> } else if (books.Count == 0) { <p>No books were found.</p> } else { <ul> @foreach (var book in books) { <li>@book.Title</li> } </ul> } @code { private List<BookSummary> books = new(); private bool isLoading = true; protected override async Task OnInitializedAsync() { try { books = await Http.GetFromJsonAsync<List<BookSummary>>( "api/Books") ?? new(); } finally { isLoading = false; } } private sealed class BookSummary { public string Title { get; set; } = string.Empty; } } 

MY SUBSCRIPTIONS= using GymManagement.Application.DTOs; using GymManagement.Application.Services; using GymManagement.Domain.RepositoryContracts; namespace GymManagement.Application.Services.Implementation; public class SubscriptionService : ISubscriptionService { private readonly ISubscriptionRepository _subscriptionRepository; public SubscriptionService( ISubscriptionRepository subscriptionRepository) { _subscriptionRepository = subscriptionRepository; } public async Task<List<MyMembershipResponseDto>> GetMyMembershipsAsync( Guid userId, CancellationToken cancellationToken) { if (userId == Guid.Empty) { return new List<MyMembershipResponseDto>(); } var subscriptions = await _subscriptionRepository.GetMyMembershipsAsync( userId, cancellationToken); var today = DateOnly.FromDateTime(DateTime.UtcNow); return subscriptions.Select(s => { // Derive an expired display status if the stored status // has not yet been updated by a background process. var displayStatus = s.Status; if (s.Status == "Active" && s.EndDate < today) { displayStatus = "Expired"; } // Example UI policy: allow cancellation only while active // and before the expiry date. var canCancel = displayStatus == "Active" && s.StartDate <= today && s.EndDate >= today; // Example UI policy: allow renewal for active or expired // memberships, but not pending or cancelled ones. var canRenew = displayStatus == "Active" || displayStatus == "Expired"; return new MyMembershipResponseDto { SubscriptionId = s.Id, GymName = s.GymCenter.GymName, PlanName = s.MembershipPlan.PlanName, StartDate = s.StartDate, ExpiryDate = s.EndDate, SubscriptionStatus = displayStatus, CanRenew = canRenew, CanCancel = canCancel }; }).ToList(); } } ======================================================================================================================= using GymManagement.Domain.Entities; using GymManagement.Domain.RepositoryContracts; using GymManagement.Infrastructure.Context; using Microsoft.EntityFrameworkCore; namespace GymManagement.Infrastructure.Repository; public class SubscriptionRepository : ISubscriptionRepository { private readonly AppDbContext _context; public SubscriptionRepository(AppDbContext context) { _context = context; } public async Task<List<Subscription>> GetMyMembershipsAsync( Guid userId, CancellationToken cancellationToken) { return await _context.Subscriptions .AsNoTracking() .Where(s => s.UserId == userId && !s.IsDeleted) .Include(s => s.GymCenter) .Include(s => s.MembershipPlan) .OrderByDescending(s => s.SubscribedOn) .ToListAsync(cancellationToken); } } =============================================================================================================================== Attendace table public class Attendance { public Guid Id { get; set; } public Guid UserId { get; set; } public Guid GymId { get; set; } public Guid SubscriptionId { get; set; } public DateTime AttendanceDate { get; set; } // Navigation properties public ApplicationUser User { get; set; } = null!; public GymCenter GymCenter { get; set; } = null!; public Subscription Subscription { get; set; } = null!; } ============================================================== modelBuilder.Entity<Attendance>() .HasOne(a => a.User) .WithMany(u => u.Attendances) .HasForeignKey(a => a.UserId) .OnDelete(DeleteBehavior.Restrict); // GymCenter 1 -> many Attendances modelBuilder.Entity<Attendance>() .HasOne(a => a.GymCenter) .WithMany(g => g.Attendances) .HasForeignKey(a => a.GymId) .OnDelete(DeleteBehavior.Restrict); // Subscription 1 -> many Attendances modelBuilder.Entity<Attendance>() .HasOne(a => a.Subscription) .WithMany(s => s.Attendances) .HasForeignKey(a => a.SubscriptionId) .OnDelete(DeleteBehavior.Restrict); using YourProject.Application.Features.Attendance.Queries.MyAttendance; using YourProject.Application.ServicesContracts; using YourProject.Domain.RepositoryContracts; namespace YourProject.Application.Services; public class AttendanceService : IAttendanceService { private readonly IAttendanceRepository _attendanceRepository; public AttendanceService( IAttendanceRepository attendanceRepository) { _attendanceRepository = attendanceRepository; } public async Task<MyAttendanceResponseDto> GetMyAttendanceAsync( Guid userId, CancellationToken cancellationToken) { if (userId == Guid.Empty) { throw new ArgumentException( "Invalid user ID.", nameof(userId)); } var totalAttendanceCount = await _attendanceRepository.GetTotalAttendanceCountAsync( userId, cancellationToken); return new MyAttendanceResponseDto { TotalAttendanceCount = totalAttendanceCount }; } } ====================================================== using Microsoft.EntityFrameworkCore; using YourProject.Domain.RepositoryContracts; using YourProject.Infrastructure.Context; namespace YourProject.Infrastructure.Repository; public class AttendanceRepository : IAttendanceRepository { private readonly AppDbContext _context; public AttendanceRepository(AppDbContext context) { _context = context; } public async Task<int> GetTotalAttendanceCountAsync( Guid userId, CancellationToken cancellationToken) { return await _context.Attendances .AsNoTracking() .CountAsync( a => a.UserId == userId, cancellationToken); } } =================================================================================== program.cs builder.Services.AddBlazoredLocalStorage(); builder.Services.AddAuthorizationCore(); builder.Services.AddCascadingAuthenticationState(); builder.Services.AddScoped<AuthenticationStateProvider,CustomAuthStateProvider>(); builder.Services.AddScoped<JwtAuthorizationHandler>(); builder.Services.AddScoped<ShowErrors>(); builder.Services.AddSweetAlert2(); builder.Services.AddScoped(sp => { var handler = sp.GetRequiredService<JwtAuthorizationHandler>(); handler.InnerHandler = new HttpClientHandler(); return new HttpClient(handler) { BaseAddress = new Uri("https://localhost:7041/api/") }; }); =================================================================== ===FOR GYMCard error show================== private async Task ShowMessageAsync( string title, string message, bool success) { await Swal.FireAsync(new SweetAlertOptions { Title = title, Text = message, Icon = success ? SweetAlertIcon.Success : SweetAlertIcon.Error }); } ================================================================= CANCELL SUBSCRIPTION public async Task<SubscriptionCommandResponse> CancelSubscriptionAsync( Guid subscriptionId, Guid userId, CancellationToken cancellationToken) { var subscription = await _subscriptionRepository.GetByIdAsync( subscriptionId, cancellationToken); if (subscription is null) { return new SubscriptionCommandResponse { Success = false, Message = "Subscription not found." }; } // Rule 1: A user can cancel only their own subscription. if (subscription.UserId != userId) { return new SubscriptionCommandResponse { Success = false, Message = "You cannot cancel another user's subscription." }; } // Rule 2: Only active subscriptions can be cancelled. if (subscription.Status != "Active") { return new SubscriptionCommandResponse { Success = false, Message = "Only active subscriptions can be cancelled." }; } // Rule 3: Calculate the refund based on the start date. var today = DateOnly.FromDateTime(DateTime.UtcNow); var daysSinceStart = today.DayNumber - subscription.StartDate.DayNumber; decimal refundPercentage = daysSinceStart >= 0 && daysSinceStart <= 7 ? 80m : 0m; decimal refundAmount = Math.Round( subscription.PricePaid * refundPercentage / 100m, 2); // Rule 4: Cancel the subscription and record the refund. subscription.Status = "Cancelled"; // Add these properties to the entity if you want to persist them. subscription.RefundAmount = refundAmount; subscription.CancelledAt = DateTime.UtcNow; await _subscriptionRepository.UpdateAsync( subscription, cancellationToken); return new SubscriptionCommandResponse { Success = true, RefundAmount = refundAmount, RefundPercentage = refundPercentage, Message = refundPercentage > 0 ? $"Subscription cancelled. You are eligible for an 80% refund of {refundAmount:C}." : "Subscription cancelled. No refund is available after the first 7 days." }; } ============================================================================== <AuthorizeView> <Authorized> <div class="sidebar">  <NavMenu /> </div> </Authorized> </AuthorizeView> ======================================================================= IN GYMCARD.RAZOR <button type="button" class="btn btn-primary mt-auto"  @onclick="ViewPlans"> <i class="bi bi-card-list me-1"></i>  View Plans </button> [Parameter] public bool IsAdmin { get; set; } [Parameter] public EventCallback<Guid> OnViewPlans { get; set; } private Task ViewPlans() => OnViewPlans.InvokeAsync(Id); IN BROWSE GYMS=== <BrowseGymCard Id="@gym.Id" GymName="@gym.GymName" Address="@gym.Address" CityName="@gym.CityName" Phone="@gym.Phone" Email="@gym.Email" OpeningTime="@gym.OpeningTime" ClosingTime="@gym.ClosingTime" TotalClassCapacity="@gym.TotalClassCapacity" LockerFacility="@gym.LockerFacility" ParkingAvailable="@gym.ParkingAvailable" Status="@gym.Status" OnViewPlans="ViewPlans" /> In BrowseGyms.razor (User page): <GymCard Id="@gym.Id" GymName="@gym.GymName" IsAdmin="false" OnViewPlans="ViewPlans" /> @code { private void ViewPlans(Guid gymId) { Navigation.NavigateTo($"/gym-membership-plans/{gymId}"); } // Keep your existing methods and properties here. } ManageGyms.razor (Admin page): <GymCard Id="@gym.Id" GymName="@gym.GymName" IsAdmin="true" OnEdit="EditGym" OnDelete="DeleteGym" /> @page "/gym-membership-plans/{GymId:guid}" ======================================================================================== NAVMENU @using Microsoft.AspNetCore.Components.Authorization <div class="top-row ps-3 navbar navbar-dark bg-secondary">  <div class="container-fluid">  <a class="navbar-brand" href="">Gym Management</a>  <button title="Navigation menu" class="navbar-toggler"  @onclick="ToggleNavMenu"> <span class="navbar-toggler-icon"></span>  </button> </div> </div> <div class="@NavMenuCssClass bg-secondary nav-scrollable shadow"  @onclick="ToggleNavMenu"> @* ADMIN SIDEBAR *@ <AuthorizeView Roles="Admin"> <Authorized> <nav class="nav flex-column">  <div class="nav-item px-3 p-1 shadow">  <NavLink class="nav-link"  href="" Match="NavLinkMatch.All"> <i class="Source：https://dev.to/lorcan_grover/blazor-documentation-component-lifecycle-592e
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