R29/WpfApp29/MainContext.cs

using Microsoft.EntityFrameworkCore;
using WpfApp29.Models;

namespace WpfApp29
{
    internal class MainContext : DbContext
    {
        public MainContext() : base()
        {
            //Database.EnsureDeleted();
            Database.EnsureCreated();
        }
        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseLazyLoadingProxies();
            optionsBuilder.UseSqlServer("Server=(localdb)\\mssqllocaldb;Database=WpfApp29;Trusted_Connection=True;");
        }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Models.Task>().HasOne(x => x.UserCreator).WithMany(t => t.TaskCreators).HasForeignKey(x => x.UserCreatorId).OnDelete(DeleteBehavior.Restrict);
            modelBuilder.Entity<Models.Task>().HasOne(x => x.UserDoer).WithMany(t => t.TaskDoers).HasForeignKey(x => x.UserDoerId).OnDelete(DeleteBehavior.Restrict);
            modelBuilder.Entity<Models.Task>().HasOne(x => x.Status).WithMany(t => t.Tasks).HasForeignKey(x => x.StatusId).OnDelete(DeleteBehavior.Restrict);
        }

        public DbSet<User> Users { get; set; }
        public DbSet<Models.Task> Tasks { get; set; }
        public DbSet<StatusTask> StatusTasks { get; set; }
    }
}