Database connectivity in ASP.net core , .NET Core DB Connection, step by step

Database connectivity in ASP.net core , .NET Core DB Connection, step by step 

Step1st:

Create ASP.NET Core Project

Step2nd:

Manage Nuget Package Manager Console 

Microsoft.EntityFrameworkCore 7.0

Microsoft.EntityFrameworkCore.SqlServer 7.0

Microsoft.EntityFrameworkCore.Tools 7.0

Step3rd:

Create Model Class

namespace WelcomeProject.Models

{

    public class Product

    {

        public int Id { get; set; }

        public string Name { get; set; }

        public decimal Price { get; set; }

    }

}

Create AppDbContext Class also under model

using Microsoft.EntityFrameworkCore;

using System.Collections.Generic;

namespace WelcomeProject.Models

{

    public class AppDbContext : DbContext

    {

        public DbSet<Product> Products { get; set; }

        private readonly IConfiguration _configuration;

        public AppDbContext(DbContextOptions<AppDbContext> options, IConfiguration configuration)

            : base(options)

        {

            _configuration = configuration;

        }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)

        {

            optionsBuilder.UseSqlServer("Server=localhost\\SQLEXPRESS;Database=mydb;Trusted_Connection=True;TrustServerCertificate=True;");

        }

    }

}

Step4th

Write this command

Add-Migration InitialCreate

Update-Database

Step5th:

Create connection string  under appSettings.json

{

  "Logging": {

    "LogLevel": {

      "Default": "Information",

      "Microsoft.AspNetCore": "Warning"

    }

  },

  "ConnectionStrings": {

    "DefaultConnection": "Server=localhost\\SQLEXPRESS;Database=mydb;Trusted_Connection=True;TrustServerCertificate=True;"

  },

  "AllowedHosts": "*"

}

Step6th:

 //Register services here

builder.Services.AddDbContext<AppDbContext>(options => options.UseSqlServer(

            builder.Configuration.GetConnectionString("DefaultConnection")

            ));

Step7th:

Register Controller under Program.cs and run this

Step8th:

Now i want to add Review on Product then i will create Review Model where Review will be child and Product will parent

Create Review Model

namespace WelcomeProject.Models

{

    public class Review

    {

        public int Id { get; set; }

        public string Content { get; set; }

        public int Rating { get; set; }

        public int ProductId { get; set; } // Foreign Key

        public Product Product { get; set; } // Navigation Property

    }

}

Change Proudct Model also

namespace WelcomeProject.Models

{

    public class Product

    {

        public int Id { get; set; }

        public string Name { get; set; }

        public decimal Price { get; set; }

        public ICollection<Review> Reviews { get; set; } // Navigation Property

    }

}

Change AppDbContext also

using Microsoft.EntityFrameworkCore;

using System.Collections.Generic;

namespace WelcomeProject.Models

{

    public class AppDbContext : DbContext

    {

        public DbSet<Product> Products { get; set; }

        public DbSet<Review> Reviews { get; set; }

        private readonly IConfiguration _configuration;

        public AppDbContext(DbContextOptions<AppDbContext> options, IConfiguration configuration)

            : base(options)

        {

            _configuration = configuration;

        }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)

        {

            optionsBuilder.UseSqlServer("Server=localhost\\SQLEXPRESS;Database=mydb;Trusted_Connection=True;TrustServerCertificate=True;");

        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)

        {

            modelBuilder.Entity<Review>()

                .HasOne(r => r.Product)

                .WithMany(p => p.Reviews)

                .HasForeignKey(r => r.ProductId);

        }

    }

}

Step9th:

Add following Command

Add-Migration AddReviewTable

Update-Database

Step10th:

Create Review Controller