What is Entity Framework Code-First approach?

1. public class Blog { public int BlogId { get; set; } public string Title { get; set; } public string Content { get; set; } public ICollection<Post> Posts { get; set; } } public class Post { public int PostId { get; set; } public string Title { get; set; } public string Content { get; set; } public int BlogId { get; set; } public Blog Blog { get; set; } }

2. Create a Database Context:

   • Create a class that derives from DbContext. This class represents the database context and includes properties for each entity set.
   csharp

   public class BlogDbContext : DbContext { public DbSet<Blog> Blogs { get; set; } public DbSet<Post> Posts { get; set; } }

3. Configure the Database Connection:

   • Specify the connection string or database provider in the application configuration.
   csharp

   services.AddDbContext<BlogDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

4. Enable Migrations:

   • Use the Entity Framework command-line tools or Package Manager Console to enable migrations. Migrations are used to create and update the database schema based on changes in your entity classes.
   bash

   dotnet ef migrations add InitialCreate

5. Apply Migrations:

   • Once migrations are created, apply them to the database to create the schema.
   bash

   dotnet ef database update

6. Use the Database Context in Code:

   • Use the database context in your application code to perform CRUD (Create, Read, Update, Delete) operations.
   csharp

   using (var context = new BlogDbContext()) { var blog = new Blog { Title = "Code-First Approach", Content = "Entity Framework Code-First" }; context.Blogs.Add(blog); context.SaveChanges(); }

Entity Framework Code-First provides a flexible and intuitive way to define your data model using C# classes, and it automatically generates the corresponding database schema. It is particularly well-suited for scenarios where the application's domain model is the primary focus and can evolve independently of the database schema.