ASP.NET Source Code Demo 2

aspnet-mvc-demo2.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Entity; // DbContext
using MVCDay8.Initializers;
using System.Data.Entity.ModelConfiguration.Conventions;

namespace MVCDay8.Models
{
    public class DatabaseContext : DbContext
    {
        public DatabaseContext() : base("MVCDay8")
        {
            //0. Default Initializer
            //Database.SetInitializer<DatabaseContext>(new CreateDatabaseIfNotExists<DatabaseContext>());

            //1. DropCreateDatabaseAlways
            Database.SetInitializer<DatabaseContext>(new DropCreateDatabaseAlways<DatabaseContext>());

            //2. DropCreateDatabaseIfModelChanges
            //Database.SetInitializer<DatabaseContext>(new DropCreateDatabaseIfModelChanges<DatabaseContext>());

            //3. Custom Db Initializer
            //Database.SetInitializer<DatabaseContext>(new CustomDbInitializer());

            //4. Null Initializer
            //turning off database initializer feature for safety reasons
            //Database.SetInitializer<DatabaseContext>(null);
        }

        public DbSet<Employee> Employees { get; set; }
        public DbSet<Department> Departments { get; set; }
        public DbSet<Project> Projects { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            //0. turn off the pluralization
            //PluralizingTableNameConvention
            modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();

            //1. setting EmpId as primary key
            modelBuilder.Entity<Employee>().HasKey(x => x.EmpId);
            modelBuilder.Entity<Department>().HasKey(x => x.DepId);

            //2. setting a custom table name
            modelBuilder.Entity<Employee>().ToTable("Employee_tbl");
            modelBuilder.Entity<Department>().ToTable("Departments");

            //3. changing column name, type, character restriction, not null
            modelBuilder.Entity<Employee>()
                .Property(x => x.LastName)
                .HasColumnName("EmployeeLN")
                .HasColumnType("varchar")
                .HasMaxLength(50)
                .IsRequired();

            //4. configuring many-to-many relationship
            modelBuilder.Entity<Employee>()
                .HasMany(x => x.Projects)
                .WithMany(x => x.Employees)
                .Map(x =>
                {
                    x.MapLeftKey("EmpId");
                    x.MapRightKey("ProjectId");
                    x.ToTable("EmpProjects");
                });
        }
    }
}