Creating Database By in ASP.NET MVC by using Entity Framework Code First Approach

Take one webapplication

Now change the authentication
click on 'Change Authentication' button

Click OK

Now Project is Created

Now Open Web.Config

Following Connectionstring is created Automatically

<connectionStrings>

    <add name="DefaultConnection" connectionString="Data Source=(LocalDb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-DemoMvc-20180325102616.mdf;Initial Catalog=aspnet-DemoMvc-20180325102616;Integrated Security=True"

      providerName="System.Data.SqlClient" />

  </connectionStrings>

Just Delete it and paste the below Connection String

<connectionStrings>

    <add name="conStr" providerName="System.Data.SqlClient" connectionString="Data Source=My-PC; Initial Catalog=OnlineShopping; Integrated Security=True; MultipleActiveResultSets=True;"></add>

  </connectionStrings>

Up to know we don't create Database in sql-server.

Here  Initial Catalog=OnlineShopping; => is a database name know we creating.

Remove that Name and give what you want (or) Keep that

Next 

My-PC; => it is my local sql-server name.

Web.config is completed.

Now Right click on "Model"  add a Class and give a name it 'Product'.

Add this two namespaces

using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

[Table("Products")]
    public class Product
    {
        [Key]
        public int ProductID { get; set; }
        public string ProductName { get; set; }
        public DateTime ManufactureDate { get; set; }
        public Int64 Cost { get; set; }
   }

[Table("Products")] :- Products is a table name.

[Key] :- Defines it is a Primary Key.

Now Right click on model add another class  and give a name it Company.

Add that two name spaces what we add on product class

and copy this code

 [Table("Company")]
    public class Company
    {
       [Key]
        public int CompanyID { get; set; }
        public string Name { get; set; }
        public Product Product { get; set; }
    }



        public Product Product { get; set; } => This is a foreign key relation it makes what are the primary keys in product class are become a  foreign keys in Company class

Also add same relation in product class


Now goto Model add another class name it ShoppingDbcontext.

"The class that derives DbContext is called context class in entity framework. DbContext is an important class in Entity Framework API. It is a bridge between your domain or entity classes and the database.DbContext is the primary class that is responsible for interacting with the database."

using System.Data.Entity; add this name space.

and inherit the shoppingcontext to DbContext
eg:-
public class ShoppinDbcontext : DbContext

Copy and paste below code:

public class ShoppinDbcontext : DbContext
    {
        public ShoppinDbcontext()
            :base("conStr")
        {

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


    }

conStr :- is a ConnectionString name what we give in Web.config.

Now Right click on Controller add an empty MVC Controller.
using DemoMvc.Models; add this namespace

DemoMvc:- ProjectName

Now Create an object for Dbcontext and add all model classes to this controller.

ShoppinDbcontext db = new ShoppinDbcontext();

With this object we can add model classes to the controller.

copy below code

   public class DefaultController : Controller
    {
        ShoppinDbcontext db = new ShoppinDbcontext();
        // GET: Default
        public ActionResult Index()
        {
            db.Products.ToList();
            db.Company.ToList();
            return View();
        }
    }


Now Right click on Index() Controller and select 'AddView' Option.

Just Click on Add Button.

Now Index.cshtml is created

@{

    ViewBag.Title = "Index";

}

<h2>Index</h2>

Just Reneame <h2>Index</h2>  

Like <h2>DataBase Created</h2>  

Now Just Hit F5

Database is Created 

 go to Sql-Server and check the database name.