Database context

The main entry point for EF would be any class that inherits the Microsoft.EntityFrameworkCore.DbContext class. Let's create a class called BlogContext and inherit the same. We will keep the context and other EF related configurations inside the Data folder. Create a Data folder in the project, and also create BlogContext.cs inside this folder:

    public class BlogContext: DbContext
    {
      public BlogContext(DbContextOptions<BlogContext> options)
        : base(options)
      {     
      }

      public DbSet<Blog> Blogs { get; set; }
      public DbSet<Post> Posts { get; set; }
    }

EF interprets DbSet<T> as a database table; we have created a DbSet<T> property for all the entities for our blogging system. We usually name the properties in plural form as the property will hold list of entities, and EF will be using those property names while creating tables in the database.

Creating a DbSet for a parent entity is enough for EF to identify the dependent entities and create corresponding tables for us. EF will be using plural form while deciding table names.

.NET developers and SQL developers debate plural table names and often end up creating entities with two different conventions. As a framework, EF supports those scenarios as well. We could override the default plural naming behavior using Fluent API. Refer to the following Fluent API code:

    public class BlogContext: DbContext
    {
      ...
      protected override void OnModelCreating(ModelBuilder modelBuilder)
      {
        modelBuilder.Entity<Blog>().ToTable("Blog");
        modelBuilder.Entity<Post>().ToTable("Post");
      }
    }

We have created a database context and configured the data models in it. You may notice we cannot see any connection string pointing to the database. It could have been done using the OnConfiguring() method with a hard-coded connection string, but it would not be an ideal implementation. Rather, we will use built-in dependency injection support from .NET Core to configure the same in the next section.