RKIS/Task1/Model/TaskContext.cs

using System;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;

// Code scaffolded by EF Core assumes nullable reference types (NRTs) are not used or disabled.
// If you have enabled NRTs for your project, then un-comment the following line:
// #nullable disable

namespace Task1
{
    public partial class TaskContext : DbContext
    {
        public TaskContext()
        {
            Database.EnsureCreated();
        }

        public TaskContext(DbContextOptions<TaskContext> options)
            : base(options)
        {
        }

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

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            if (!optionsBuilder.IsConfigured)
            {
                optionsBuilder.UseLazyLoadingProxies();
                optionsBuilder.UseSqlServer("Data Source=(localdb)\\mssqllocaldb; Initial Catalog=Task;Trusted_Connection=True;");
            }
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<StatusTask>(entity =>
            {
                entity.HasKey(e => e.Id);

                entity.Property(e => e.Name)
                    .IsRequired()
                    .HasMaxLength(50);
            });

            modelBuilder.Entity<Task>(entity =>
            {
                entity.HasKey(e => e.TaskId);

                entity.Property(e => e.Date).HasColumnType("date");

                entity.Property(e => e.Description)
                    .IsRequired()
                    .HasMaxLength(50);

                entity.Property(e => e.Name)
                    .IsRequired()
                    .HasMaxLength(50);

                entity.HasOne(d => d.StatusTask1)
                    .WithMany(p => p.Task)
                    .HasForeignKey(d => d.StatusTaskId)
                    .OnDelete(DeleteBehavior.ClientSetNull)
                    .HasConstraintName("FK_Task_StatusTask");

                entity.HasOne(d => d.UserAcceptedTask)
                    .WithMany(p => p.TaskUserAcceptedTask)
                    .HasForeignKey(d => d.UserAcceptedTaskId)
                    .OnDelete(DeleteBehavior.ClientSetNull)
                    .HasConstraintName("FK_Task_User2");

                entity.HasOne(d => d.UserCreatedTask)
                    .WithMany(p => p.TaskUserCreatedTask)
                    .HasForeignKey(d => d.UserCreatedTaskId)
                    .OnDelete(DeleteBehavior.ClientSetNull)
                    .HasConstraintName("FK_Task_User1");
            });

            modelBuilder.Entity<User>(entity =>
            {
                entity.HasKey(e => e.UserId);

                entity.Property(e => e.Login)
                    .IsRequired()
                    .HasMaxLength(50);

                entity.Property(e => e.Name)
                    .IsRequired()
                    .HasMaxLength(50);

                entity.Property(e => e.Password)
                    .IsRequired()
                    .HasMaxLength(50);

                entity.Property(e => e.Patronimyc).HasMaxLength(50);

                entity.Property(e => e.Phone)
                    .IsRequired()
                    .HasMaxLength(12)
                    .IsUnicode(false)
                    .IsFixedLength();

                entity.Property(e => e.Surname)
                    .IsRequired()
                    .HasMaxLength(50);
            });

            OnModelCreatingPartial(modelBuilder);
        }

        partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
    }
}