Entity Framework Core Crash Course | C# .NET EF Core Tutorial for Beginners (Code First)

Introduction

This tutorial provides a comprehensive guide to using Entity Framework Core (EF Core) with C# and .NET, focusing on the Code First approach to building a Blog Manager console application. By following these steps, you'll learn how to set up your development environment, create models, manage migrations, and perform CRUD operations in a SQLite database.

Step 1: Install Visual Studio Code

1. Visit the Visual Studio Code website: Download Visual Studio Code.
2. Choose the appropriate version for your operating system and install it.

Step 2: Install .NET Core SDK

1. Go to the .NET Core download page: Download .NET Core.
2. Select the latest version of the .NET Core SDK and install it on your machine.

Step 3: Install Required Visual Studio Code Extensions

1. Open Visual Studio Code.
2. Go to the Extensions view by clicking on the Extensions icon in the sidebar or pressing Ctrl+Shift+X.
3. Search for and install the following extensions:
   • SQLite3 editor: Sqlite3 Editor
   • C# Dev Kit: C# Dev Kit

Step 4: Install Entity Framework Core Packages

1. Open a terminal in Visual Studio Code (`Ctrl + ``).
2. Create a new project using the .NET CLI:

   dotnet new console -n BlogManager
   cd BlogManager
   

3. Install the necessary Entity Framework packages:

   dotnet add package Microsoft.EntityFrameworkCore.Design
   dotnet add package Microsoft.EntityFrameworkCore.Sqlite
   dotnet tool install --global dotnet-ef
   

Step 5: Create Models Using Code First Approach

1. Create a new class for your model, for example, BlogPost.cs:

   public class BlogPost
   {
       public int Id { get; set; }
       public string Title { get; set; }
       public string Content { get; set; }
       public DateTime CreatedAt { get; set; }
   }
   

2. Define a DbContext class to manage your entities:

   public class BlogContext : DbContext
   {
       public DbSet<BlogPost> BlogPosts { get; set; }
   
       protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
       {
           optionsBuilder.UseSqlite("DataSource=blog.db");
       }
   }
   

Step 6: Create and Apply Migrations

1. In the terminal, create a migration:

   dotnet ef migrations add InitialCreate
   

2. Apply the migration to the database:

   dotnet ef database update
   

Step 7: Build Console Application UI

1. Design a simple console interface to collect user input for blog posts.
2. Use Console.ReadLine() to read user input and Console.WriteLine() for outputs.

Step 8: Implement CRUD Operations

1. Create: Add a method to add a new blog post.

   public void AddBlogPost(BlogPost post)
   {
       using (var db = new BlogContext())
       {
           db.BlogPosts.Add(post);
           db.SaveChanges();
       }
   }
   

2. Read: Implement a method to retrieve and display blog posts.

   public List<BlogPost> GetBlogPosts()
   {
       using (var db = new BlogContext())
       {
           return db.BlogPosts.ToList();
       }
   }
   

3. Update: Create a method to update existing blog posts.

   public void UpdateBlogPost(BlogPost post)
   {
       using (var db = new BlogContext())
       {
           db.BlogPosts.Update(post);
           db.SaveChanges();
       }
   }
   

4. Delete: Write a method to delete a blog post.

   public void DeleteBlogPost(int id)
   {
       using (var db = new BlogContext())
       {
           var post = db.BlogPosts.Find(id);
           if (post != null)
           {
               db.BlogPosts.Remove(post);
               db.SaveChanges();
           }
       }
   }
   

Conclusion

By following these steps, you've set up a Blog Manager console application using Entity Framework Core with a Code First approach. You learned how to install necessary tools, create a SQLite database, manage migrations, and perform basic CRUD operations. As a next step, consider expanding your application by adding features like user authentication or a web interface using ASP.NET Core. For more in-depth knowledge, refer to the Entity Framework Documentation.