Asp.net core entity framework database first approach CRUD application

 How to achieve entity framework in asp.net core using database first approach scaffolding mechanism reverse enginner (existing database)

Below mentioned tools required for this tutorial

·         Visual studio 2017

·         Core 2.0

·         Sql server V18.2

Steps to achieve database first approach:

1. Open visual studio 2017 and create new ASP.NET Core MVC project in the name of MyDBFirstApp

 

2. Create database, table in sql server management studio

Database: ecommerce

Table: userdetails

CREATE TABLE [dbo].[userdetails](
	[Id] [int] IDENTITY(1,1) NOT NULL,
	[Name] [varchar](50) NULL,
	[Email] [varchar](50) NULL,
	[Password] [varchar](50) NULL,
	[Mobile] [varchar](50) NULL,
PRIMARY KEY CLUSTERED 
(
	[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

3. Execute the below script in Package Manager Console

Scaffold-DbContext "Server=(local)\SQLEXPRESS01;Database=ecommerce;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models

Now model folder contains two more files in the name of ecommerceContext.cs, Userdetails.cs.

Update below mentioned code in ecommerceContext.cs class constructor

using System;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;

namespace MyDBFirstApp.Models
{
    public partial class ecommerceContext : DbContext
    {
        public virtual DbSet<Userdetails> Userdetails { get; set; }

        public ecommerceContext(DbContextOptions<ecommerceContext> options) : base(options)
        {

        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Userdetails>(entity =>
            {
                entity.ToTable("userdetails");

                entity.Property(e => e.Email)
                    .HasMaxLength(50)
                    .IsUnicode(false);

                entity.Property(e => e.Mobile)
                    .HasMaxLength(50)
                    .IsUnicode(false);

                entity.Property(e => e.Name)
                    .HasMaxLength(50)
                    .IsUnicode(false);

                entity.Property(e => e.Password)
                    .HasMaxLength(50)
                    .IsUnicode(false);
            });
        }
    }
}

4. Create connection string in Appsetting.json file

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "ConnectionStrings": {
    "DevConnection": "Server=(local)\\SQLEXPRESS01;Database=ecommerce;Trusted_Connection=True;MultipleActiveResultSets=True;"
  }
}

5. Configure db context connection string in startup.cs file ConfigureServices function.

services.AddDbContext<ecommerceContext>(options =>

           options.UseSqlServer(Configuration.GetConnectionString("DevConnection")));

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using MyDBFirstApp.Models;
using Microsoft.EntityFrameworkCore;

namespace MyDBFirstApp
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            services.AddDbContext<ecommerceContext>(options =>
           options.UseSqlServer(Configuration.GetConnectionString("DevConnection")));
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseBrowserLink();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }

            app.UseStaticFiles();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}

6. Right click the controller folder and create Mvc controller views using entity framework.

 

Now Asp.net Scaffolding code generation created all CRUD application-related files in View and controller folder.

Finally, run your  asp.net core crud application using entity framework.