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CC#

•Created by Luciferno on 11/9/2022 in #help

Value binding

4 replies

CC#

•Created by Luciferno on 10/19/2022 in #help

EF Core many-to-many relation error

6 replies

CC#

•Created by Luciferno on 9/21/2022 in #help

How to keep track of third property in Many-To-Many

I have 2 models one that is Reservation and one that is Menu, They have a many-to-many relation but I wanna keep track on the reservation how many times one menu is ordered for that resrevation. This is my current many-to-many table :

        public int ReservationId { get; set; }
        public Reservation Reservation { get; set; }

        public int MenuId { get; set; }
        public int TimesOrdered { get; set; } <-- this property needs to keep track of how many times a menu has been ordered.
        public Menu Menu { get; set; }

        public int ReservationId { get; set; }
        public Reservation Reservation { get; set; }

        public int MenuId { get; set; }
        public int TimesOrdered { get; set; } <-- this property needs to keep track of how many times a menu has been ordered.
        public Menu Menu { get; set; }

This is my current OnModelCreating for that table

        modelBuilder.Entity<Reservation>()
            .HasMany(x => x.Menus)
            .WithMany(x => x.Reservations)
            .UsingEntity<ReservationMenu>(
                rm => rm.HasOne(x => x.Menu).WithMany().HasForeignKey(k => k.MenuId),
                rm => rm.HasOne(x => x.Reservation).WithMany().HasForeignKey(k => k.ReservationId),
                rm =>
                {
                    rm.HasKey(p => new { p.MenuId, p.ReservationId });
                }
            );

        modelBuilder.Entity<Reservation>()
            .HasMany(x => x.Menus)
            .WithMany(x => x.Reservations)
            .UsingEntity<ReservationMenu>(
                rm => rm.HasOne(x => x.Menu).WithMany().HasForeignKey(k => k.MenuId),
                rm => rm.HasOne(x => x.Reservation).WithMany().HasForeignKey(k => k.ReservationId),
                rm =>
                {
                    rm.HasKey(p => new { p.MenuId, p.ReservationId });
                }
            );

I am kinda stuck on how to approach this.

4 replies

CC#

•Created by Luciferno on 9/18/2022 in #help

EF-Core data reference [Answered]

So for school we have to make a Restaurant management system. Now I am working on Reservations with the following model

        [Key]
        public int ReservationID { get; set; }

        public string? FirstName { get; set; }

        public string? LastName { get; set; }

        public string? Adress { get; set; }

        public string? City { get; set; }

        public string? Email { get; set; }

        public int GuestsComing { get; set; }

        public DateTime? Date { get; set; }

        public TimeSpan? Time { get; set; }

        public List<Menu> ChoosenMenus { get; set; }

        public decimal FoodPrice { get; set; }

        public int UserFK { get; set; }

        [Key]
        public int ReservationID { get; set; }

        public string? FirstName { get; set; }

        public string? LastName { get; set; }

        public string? Adress { get; set; }

        public string? City { get; set; }

        public string? Email { get; set; }

        public int GuestsComing { get; set; }

        public DateTime? Date { get; set; }

        public TimeSpan? Time { get; set; }

        public List<Menu> ChoosenMenus { get; set; }

        public decimal FoodPrice { get; set; }

        public int UserFK { get; set; }

But the problem I encounter is that the list ChoosenMenus exists of Menus that are already saved in my database but when I make a post request it still tries to add the menu's This is my DbContext regarding the Reservation model so far

        modelBuilder.Entity<Reservation>()
            .HasOne<UserInfo>()
            .WithMany()
            .HasForeignKey(x => x.UserFK);

        modelBuilder.Entity<Reservation>()
            .HasOne<UserInfo>()
            .WithMany()
            .HasForeignKey(x => x.UserFK);

So I somehow need to make a reference to the already exisiting menus instead of adding them but I dont really know how to

64 replies

CC#

•Created by Luciferno on 9/14/2022 in #help

Deserialization Error

9 replies

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