Getting Started with EF Core on ASP.NET Core with an Existing Database

• 10/27/2016
• 5 minutes to read
• Contributors
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In this article

1. Prerequisites
2. Create a new project
3. Install Entity Framework
4. Reverse engineer your model
5. Register your context with dependency injection
6. Create a controller
7. Run the application

Important

The .NET Core SDK no longer supports project.json or Visual Studio 2015. Everyone doing .NET Core development is encouraged to migrate from project.json to csproj and Visual Studio 2017.1

In this walkthrough, you will build an ASP.NET Core MVC application that performs basic data access using Entity Framework. You will use reverse engineering to create an Entity Framework model based on an existing database.

Tip

You can view this article's sample on GitHub.

Prerequisites

The following prerequisites are needed to complete this walkthrough:

• Visual Studio 2017 15.3 with these workloads:
  • ASP.NET and web development (under Web & Cloud)
  • .NET Core cross-platform development (under Other Toolsets)
• .NET Core 2.0 SDK.
• Blogging database

Blogging database

This tutorial uses a Blogging database on your LocalDb instance as the existing database.

Tip

If you have already created the Blogging database as part of another tutorial, you can skip these steps.

• Open Visual Studio
• Tools -> Connect to Database...
• Select Microsoft SQL Server and click Continue
• Enter (localdb)\mssqllocaldb as the Server Name
• Enter master as the Database Name and click OK
• The master database is now displayed under Data Connections in Server Explorer
• Right-click on the database in Server Explorer and select New Query
• Copy the script, listed below, into the query editor
• Right-click on the query editor and select Execute

SQL

CREATE DATABASE [Blogging];
GO

USE [Blogging];
GO

CREATE TABLE [Blog] (
    [BlogId] int NOT NULL IDENTITY,
    [Url] nvarchar(max) NOT NULL,
    CONSTRAINT [PK_Blog] PRIMARY KEY ([BlogId])
);
GO

CREATE TABLE [Post] (
    [PostId] int NOT NULL IDENTITY,
    [BlogId] int NOT NULL,
    [Content] nvarchar(max),
    [Title] nvarchar(max),
    CONSTRAINT [PK_Post] PRIMARY KEY ([PostId]),
    CONSTRAINT [FK_Post_Blog_BlogId] FOREIGN KEY ([BlogId]) REFERENCES [Blog] ([BlogId]) ON DELETE CASCADE
);
GO

INSERT INTO [Blog] (Url) VALUES
('http://blogs.msdn.com/dotnet'),
('http://blogs.msdn.com/webdev'),
('http://blogs.msdn.com/visualstudio')
GO

Create a new project

• Open Visual Studio 2017
• File -> New -> Project...
• From the left menu select Installed -> Templates -> Visual C# -> Web
• Select the ASP.NET Core Web Application (.NET Core) project template
• Enter EFGetStarted.AspNetCore.ExistingDb as the name and click OK
• Wait for the New ASP.NET Core Web Application dialog to appear
• Under ASP.NET Core Templates 2.0 select the Web Application (Model-View-Controller)
• Ensure that Authentication is set to No Authentication
• Click OK

Install Entity Framework

To use EF Core, install the package for the database provider(s) you want to target. This walkthrough uses SQL Server. For a list of available providers see Database Providers.4

• Tools > NuGet Package Manager > Package Manager Console
• Run Install-Package Microsoft.EntityFrameworkCore.SqlServer
2

We will be using some Entity Framework Tools to create a model from the database. So we will install the tools package as well:

• Run Install-Package Microsoft.EntityFrameworkCore.Tools

We will be using some ASP.NET Core Scaffolding tools to create controllers and views later on. So we will install this design package as well:

• Run Install-Package Microsoft.VisualStudio.Web.CodeGeneration.Design

Reverse engineer your model

Now it's time to create the EF model based on your existing database.

• Tools –> NuGet Package Manager –> Package Manager Console
• Run the following command to create a model from the existing database:
19

PowerShell

Scaffold-DbContext "Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models

If you receive an error stating The term 'Scaffold-DbContext' is not recognized as the name of a cmdlet, then close and reopen Visual Studio.1

Tip

You can specify which tables you want to generate entities for by adding the -Tablesargument to the command above. E.g. -Tables Blog,Post.

The reverse engineer process created entity classes (Blog.cs & Post.cs) and a derived context (BloggingContext.cs) based on the schema of the existing database.1

The entity classes are simple C# objects that represent the data you will be querying and saving.

C#

using System;
using System.Collections.Generic;

namespace EFGetStarted.AspNetCore.ExistingDb.Models
{
    public partial class Blog
    {
        public Blog()
        {
            Post = new HashSet<Post>();
        }

        public int BlogId { get; set; }
        public string Url { get; set; }

        public virtual ICollection<Post> Post { get; set; }
    }
}

The context represents a session with the database and allows you to query and save instances of the entity classes.

C#

public partial class BloggingContext : DbContext
{
   public virtual DbSet<Blog> Blog { get; set; }
   public virtual DbSet<Post> Post { get; set; }

   protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
   {
       if (!optionsBuilder.IsConfigured)
       {
           #warning To protect potentially sensitive information in your connection string, you should move it out of source code. See http://go.microsoft.com/fwlink/?LinkId=723263 for guidance on storing connection strings.
           optionsBuilder.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;");
       }
   }

   protected override void OnModelCreating(ModelBuilder modelBuilder)
   {
       modelBuilder.Entity<Blog>(entity =>
       {
           entity.Property(e => e.Url).IsRequired();
       });

       modelBuilder.Entity<Post>(entity =>
       {
           entity.HasOne(d => d.Blog)
               .WithMany(p => p.Post)
               .HasForeignKey(d => d.BlogId);
       });
   }
}

Register your context with dependency injection

The concept of dependency injection is central to ASP.NET Core. Services (such as BloggingContext) are registered with dependency injection during application startup. Components that require these services (such as your MVC controllers) are then provided these services via constructor parameters or properties. For more information on dependency injection see the Dependency Injection article on the ASP.NET site.

Remove inline context configuration

In ASP.NET Core, configuration is generally performed in Startup.cs. To conform to this pattern, we will move configuration of the database provider to Startup.cs.1

• Open Models\BloggingContext.cs
• Delete the OnConfiguring(...) method
2

C#

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
    #warning To protect potentially sensitive information in your connection string, you should move it out of source code. See http://go.microsoft.com/fwlink/?LinkId=723263 for guidance on storing connection strings.
    optionsBuilder.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;");
}

• Add the following constructor, which will allow configuration to be passed into the context by dependency injection

C#

public BloggingContext(DbContextOptions<BloggingContext> options)
    : base(options)
{ }

Register and configure your context in Startup.cs

In order for our MVC controllers to make use of BloggingContext we are going to register it as a service.

• Open Startup.cs
• Add the following using statements at the start of the file

C#

using EFGetStarted.AspNetCore.ExistingDb.Models;
using Microsoft.EntityFrameworkCore;

Now we can use the AddDbContext(...) method to register it as a service.

• Locate the ConfigureServices(...) method
• Add the following code to register the context as a service

C#

// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc();

    var connection = @"Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;ConnectRetryCount=0";
    services.AddDbContext<BloggingContext>(options => options.UseSqlServer(connection));
}

Tip

In a real application you would typically put the connection string in a configuration file. For the sake of simplicity, we are defining it in code. For more information, see Connection Strings.2

Create a controller

Next, we'll enable scaffolding in our project.

• Right-click on the Controllers folder in Solution Explorer and select Add -> Controller...
• Select Full Dependencies and click Add
• You can ignore the instructions in the ScaffoldingReadMe.txt file that opens
4

Now that scaffolding is enabled, we can scaffold a controller for the Blog entity.

• Right-click on the Controllers folder in Solution Explorer and select Add -> Controller...
• Select MVC Controller with views, using Entity Framework and click Ok
• Set Model class to Blog and Data context class to BloggingContext
• Click Add
3

Run the application

You can now run the application to see it in action.

• Debug -> Start Without Debugging
• The application will build and open in a web browser
• Navigate to /Blogs
• Click Create New
• Enter a Url for the new blog and click Create
1

ebay delivery aspcore

.asp core project ebay_track

search by shipping date

additional filters for search

dropdown list is sorted

sort by item

sort by date

every action is logged by history controller

dropdown list item is selected based on record

do a final validation before search form submission, 

found error start date entered is later than end date

input type: text, date, number, select list

----------------------------------------------------------------------------------------
delivery controller

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.EntityFrameworkCore;
using ebay_track.Models;
using Microsoft.AspNetCore.Http;

namespace ebay_track.Controllers
{
    public class DeliveriesController : Controller
    {
        private readonly ebayContext _context;

        public DeliveriesController(ebayContext context)
        {
            _context = context;
        }

        public async Task<IActionResult> Index()
        {
            ViewBag.c_end = DateTime.Now;
            ViewBag.c_begin = "";

            var ebayContext = _context.Delivery.Include(d => d.Item).
                Where(x => x.Arrived == "N" &&x.CaseClosed!="Y");

            ViewBag.ItemId = await _context.Item.ToListAsync();

            return View(await ebayContext.ToListAsync());
        }

        [HttpPost]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> Index(IFormCollection collection)
        {         

            var search_result = new List<Delivery>();

            var C_begin = DateTime.Now.AddYears(-10);
            var C_end = DateTime.Now;

            if (collection["begin"] != "") { C_begin = Convert.ToDateTime(collection["begin"]); }
            if (collection["end"] != "") { C_end = Convert.ToDateTime(collection["end"]); }

            ViewBag.c_end = C_end;
            ViewBag.c_begin = C_begin;
            ViewBag.ItemId = await _context.Item.ToListAsync();

            //filter by calendar
            search_result = await _context.Delivery.Include(d => d.Item).
                Where(x => DateTime.Compare(C_begin, x.ShippingDate) < 0 && DateTime.Compare(C_end, x.ShippingDate) > 0).ToListAsync();

            //filter by delivery status
         
            var delivery_status = collection["delivery"].ToString();

            if (delivery_status=="Y"||delivery_status=="N")
            {             
                search_result = search_result.Where(x => x.Arrived == delivery_status).ToList();
            }

            //filter by case_closed
            var case_closed_status = collection["case_closed"].ToString();

            if (case_closed_status=="Y")
            {
                search_result = search_result.Where(x => x.CaseClosed == "Y").ToList();
            }
            else if(case_closed_status=="N")
            {
                search_result = search_result.Where(x => x.CaseClosed != "Y").ToList();
            }
            else
            { }

            //filter by item
            if (collection["item_select"] != "")
            {
                var item_number = Convert.ToInt32(collection["item_select"]);

                search_result = search_result.Where(x => x.ItemId == item_number).ToList();
            }

            return View(search_result);
        }

        // GET: Deliveries/Details/5
        public async Task<IActionResult> Details(int? id)
        {
            if (id == null)
            {
                return NotFound();
            }

            var delivery = await _context.Delivery
                .Include(d => d.Item)
                .SingleOrDefaultAsync(m => m.Id == id);
            if (delivery == null)
            {
                return NotFound();
            }

            return View(delivery);
        }

        // GET: Deliveries/Create
        public async Task<IActionResult> Create()
        {

            ViewBag.ItemId = await _context.Item.ToListAsync();
            return View();
        }

        // POST: Deliveries/Create
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see http://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> Create([Bind("Id,ItemId,ShippingDate,DeliveryDate,Qty,Tracking,Arrived,CaseClosed")] Delivery delivery)
        {
            if (ModelState.IsValid)
            {
                _context.Add(delivery);
                await _context.SaveChangesAsync();

                //------------------------------------------------------
                var item = await _context.Item.SingleOrDefaultAsync(m => m.Id == delivery.ItemId);

                var history = new History
                {
                    ActionDate = DateTime.Now,
                    ActionType = "Create",
                    Item = item.Name,
                    Qty = delivery.Qty,
                    Tracking = delivery.Tracking,
                    DeliveryDate=delivery.DeliveryDate,
                    ShippingDate=delivery.ShippingDate
                };

                HttpContext.Session.SetObjectAsJson("action", history);
                //redirect to history controller to save a record of the action
                return RedirectToAction("receiver", "Histories");
                //------------------------------------------------------
            }
            ViewData["ItemId"] = new SelectList(_context.Item, "Id", "Name", delivery.ItemId);
            return View(delivery);
        }

        // GET: Deliveries/Edit/5
        public async Task<IActionResult> Edit(int? id)
        {
            if (id == null)
            {
                return NotFound();
            }

            var delivery = await _context.Delivery.SingleOrDefaultAsync(m => m.Id == id);
            if (delivery == null)
            {
                return NotFound();
            }
            ViewData["ItemId"] = new SelectList(_context.Item, "Id", "Name", delivery.ItemId);
            return View(delivery);
        }

        // POST: Deliveries/Edit/5
        // To protect from overposting attacks, please enable the specific properties you want to bind to, for
        // more details see http://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> Edit(int id, [Bind("Id,ItemId,Qty,ShippingDate,DeliveryDate,Tracking,Arrived,CaseClosed")] Delivery delivery)
        {
            if (id != delivery.Id)
            {
                return NotFound();
            }

            if (ModelState.IsValid)
            {
                try
                {
                    _context.Update(delivery);
                    await _context.SaveChangesAsync();
                }
                catch (DbUpdateConcurrencyException)
                {
                    if (!DeliveryExists(delivery.Id))
                    {
                        return NotFound();
                    }
                    else
                    {
                        throw;
                    }
                }
                //------------------------------------------------------
                var item = await _context.Item.SingleOrDefaultAsync(m => m.Id == delivery.ItemId);

                var history = new History
                {
                    ActionDate = DateTime.Now,
                    ActionType = "Edit",
                    Item = item.Name,
                    Qty = delivery.Qty,
                    Tracking = delivery.Tracking,
                    DeliveryDate = delivery.DeliveryDate,
                    ShippingDate = delivery.ShippingDate
                };

                HttpContext.Session.SetObjectAsJson("action", history);
                //redirect to history controller to save a record of the action
                return RedirectToAction("receiver", "Histories");
                //-----------------------------------------------------------
            }
            ViewData["ItemId"] = new SelectList(_context.Item, "Id", "Name", delivery.ItemId);
            return View(delivery);
        }

        // GET: Deliveries/Delete/5
        public async Task<IActionResult> Delete(int? id)
        {
            if (id == null)
            {
                return NotFound();
            }

            var delivery = await _context.Delivery
                .Include(d => d.Item)
                .SingleOrDefaultAsync(m => m.Id == id);
            if (delivery == null)
            {
                return NotFound();
            }

            return View(delivery);
        }

        // POST: Deliveries/Delete/5
        [HttpPost, ActionName("Delete")]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> DeleteConfirmed(int id)
        {
            var delivery = await _context.Delivery.SingleOrDefaultAsync(m => m.Id == id);
            _context.Delivery.Remove(delivery);
            await _context.SaveChangesAsync();

            //------------------------------------------------------
            var item = await _context.Item.SingleOrDefaultAsync(m => m.Id == delivery.ItemId);

            var history = new History
            {
                ActionDate = DateTime.Now,
                ActionType = "Delete",
                Item = item.Name,
                Qty = delivery.Qty,
                Tracking = delivery.Tracking,
                DeliveryDate = delivery.DeliveryDate,
                ShippingDate = delivery.ShippingDate
            };

            HttpContext.Session.SetObjectAsJson("action", history);
            //redirect to history controller to save a record of the action
            return RedirectToAction("receiver", "Histories");
            //------------------------------------------------------
        }

        private bool DeliveryExists(int id)
        {
            return _context.Delivery.Any(e => e.Id == id);
        }
    }
}

---------------------------------------------------------------------
history controller function

public async Task<IActionResult> receiver()
        {
            var lastAction = HttpContext.Session.GetObjectFromJson<History>("action");
            _context.Add(lastAction);
            await _context.SaveChangesAsync();
            return RedirectToAction("Index", "Deliveries");
        }

-----------------------------------------------------------------------
SessionExtensions.cs

using Microsoft.AspNetCore.Http;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace ebay_track.Models
{
    public static class SessionExtensions
    {
        public static void SetObjectAsJson(this ISession session, string key, object value)
        {
            session.SetString(key, JsonConvert.SerializeObject(value));
        }

        public static T GetObjectFromJson<T>(this ISession session, string key)
        {
            var value = session.GetString(key);

            return value == null ? default(T) : JsonConvert.DeserializeObject<T>(value);
        }
    }
}

-----------------------------------------------------------------------

deliveries view index.cshtml

@model IEnumerable<ebay_track.Models.Delivery>

@{
    ViewData["Title"] = "Index";
}

<script src="~/lib/jquery/dist/jquery.js"></script>
<script type="text/javascript">

    var item_list = [];
    var delivery_list = [];

    $(document).ready(function () {

    $("#item_select").append(new Option("All",""));

    @foreach(var item in ViewBag.ItemId)
{
    <text>
        item_list.push(new item_class('@item.Id', '@item.Name'));
        </text>
}

          @foreach(var delivery in Model)
{
    <text>
        delivery_list.push(new delivery_class('@delivery.Id','@delivery.ShippingDate', '@delivery.DeliveryDate', '@delivery.Item.Name', '@delivery.Qty', '@delivery.Tracking', '@delivery.Arrived','@delivery.CaseClosed'));
        </text>
}

item_list.sort(function (a, b) {

    var aName = a.name.toLowerCase();
    var bName = b.name.toLowerCase();
    return ((aName < bName) ? -1 : ((aName > bName) ? 1 : 0));
        });

$.each(item_list, function () {

    $("#item_select").append(new Option(this.name, this.id));
    });

    sort_by_date();
     });

function item_class(id, name) {
    this.id = id;
    this.name = name;
    }

    function delivery_class(id, shippingDate, deliveryDate, item, qty, tracking, arrived, caseClosed) {
        this.id = id;
        this.shippingDate = shippingDate.replace("12:00:00 AM", "");
        this.deliveryDate = deliveryDate.replace("12:00:00 AM", "");
        this.item = item;
        this.qty = qty;
        this.tracking = tracking;
        this.arrived = arrived;
        this.caseClosed = caseClosed;
    }

    function check() {

        $("#error").text("");

        var begin = $("#calendar_begin").val();
        var end = $("#calendar_end").val();

        if (begin == null || end == null) { return true; }

        var begin_value = parseInt(begin.replace(/-/g, ''));
        var end_value = parseInt( end.replace(/-/g, ''));

        if (begin_value > end_value) {

            $("#error").text("begin date " + begin + " " + begin_value + " is later than end date " + end_value);
            return false;
        }

        return true;
    }

    function sort_by_item() {

        $("#display_table tbody > tr").remove();

        delivery_list.sort(function (a, b) {

            var aName = a.item.toLowerCase();
            var bName = b.item.toLowerCase();
            return ((aName < bName) ? -1 : ((aName > bName) ? 1 : 0));
        });

        populate_table();

    }

    function sort_by_date() {

        $("#display_table tbody > tr").remove();

        delivery_list.sort(function (a, b) {

            var aName = new Date( a.shippingDate);
            var bName = new Date( b.shippingDate);
            return ((aName.getTime() < bName.getTime()) ? -1 : ((aName.getTime() > bName.getTime()) ? 1 : 0));
        });

        populate_table();
    }

    function sort_by_date2() {

        $("#display_table tbody > tr").remove();

       delivery_list.sort(function (a, b) {

            var aName = new Date(a.deliveryDate);
            var bName = new Date(b.deliveryDate);
            return ((aName.getTime() < bName.getTime()) ? -1 : ((aName.getTime() > bName.getTime()) ? 1 : 0));
        });

        populate_table();
    }

    function populate_table() {

        $.each(delivery_list, function () {

            $("#display_table tbody ").append(
                "<tr><td>" + this.shippingDate +
                "</td><td>" + this.deliveryDate +
                "</td><td>" + this.item +
                "</td><td>" + this.qty +
                "</td><td>" + this.tracking +
                "</td><td>" + this.arrived +
                "</td><td>" + this.caseClosed +
                "</td><td>" + "<a href= '" + window.location.href +"/Deliveries/Edit?id=" + this.id + "'>edit</a>" +
                "</td><td>" + "<a href= '" + window.location.href +"/Deliveries/Details?id=" + this.id + "'>detail</a>" +
                "</td><td>" + "<a href= '" + window.location.href +"/Deliveries/Delete?id=" + this.id + "'>delete</a>" +
                "</td></tr>");
        });
    }
</script>

<h2>Index</h2>

<p style="color:red" id="error"></p>


<form method="post" onsubmit="return check()">
    <div class="row">
        <div class="col-md-6">
            <label>shipping date begin: @ViewBag.c_begin</label><br />
            <input type="date" class="form-control" name="begin" id="calendar_begin" />
        </div>
        <div class="col-md-6">
            <label>shipping date end: @ViewBag.c_end</label><br />
            <input type="date" class="form-control" name="end" id="calendar_end" />
        </div>
    </div>
    <hr />
    <div class="row">
        <div class="col-md-4">
            <label>delivery status</label>
            <select name="delivery" class="form-control">
                <option value="N" selected>undelivered</option>
                <option value="Y">arrived</option>
                <option value="B">both</option>
            </select>
        </div>
        <div class="col-md-4">
            <label>case closed</label>
            <select name="case_closed" class="form-control">
                <option value="N" selected>no case or case is open</option>
                <option value="Y">closed by ebay</option>
                <option value="B">both</option>
            </select>
        </div>
        <div class="col-md-4">
            <label class="control-label">Item</label>
            <select name="item_select" id="item_select" class="form-control"></select>
        </div>
    </div>
    <hr />
    <div class="row">
        <div class="col-md-8 col-md-offset-2">
            <input type="submit" value="search" class="form-control btn btn-primary" />
        </div>
    </div>
</form>

<hr/>

<p>
    <a asp-action="Create">Create New</a>
</p>
<table class="table table-hover" id="display_table">
    <thead>
        <tr>
            <th>
                @Html.DisplayNameFor(model => model.ShippingDate)
                <button type="button" class="btn btn-primary" onclick="sort_by_date()">
                    <span class="glyphicon glyphicon-sort-by-attributes"></span>
                </button>
            </th>
            <th>
                @Html.DisplayNameFor(model => model.DeliveryDate)
                <button type="button" class="btn btn-primary" onclick="sort_by_date2()">
                    <span class="glyphicon glyphicon-sort-by-attributes"></span>
                </button>
            </th>
            <th>
                @Html.DisplayNameFor(model => model.Item)
                <button type="button" class="btn btn-primary" onclick="sort_by_item()">
                    <span class="glyphicon glyphicon-sort-by-attributes"></span>
                </button>
            </th>
            <th>
                @Html.DisplayNameFor(model => model.Qty)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.Tracking)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.Arrived)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.CaseClosed)
            </th>
            <th></th>
        </tr>
    </thead>
    <tbody>
     
    </tbody>
</table>

---------------------------------------------------------------
delivery view create.cshtml

@model ebay_track.Models.Delivery

@{
    ViewData["Title"] = "Create";
}

<script src="~/lib/jquery/dist/jquery.js"></script>
<script type="text/javascript">

    var item_list = [];

$(document).ready(function () {
    @foreach(var item in ViewBag.ItemId)
{
    <text>
        item_list.push(new item_class('@item.Id', '@item.Name'));
        </text>
}

item_list.sort(function (a, b) {

    var aName = a.name.toLowerCase();
    var bName = b.name.toLowerCase();
    return ((aName < bName) ? -1 : ((aName > bName) ? 1 : 0));
});

$.each(item_list, function () {

    $("#item_select").append(new Option(this.name, this.id));
});
     });

function item_class(id, name) {
    this.id = id;
    this.name = name;
}

</script>

<h2>Create</h2>

<h4>Delivery</h4>
<hr />
<div class="row">
    <div class="col-md-4">
        <form asp-action="Create">
            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
            <div class="form-group">

                <label asp-for="ItemId" class="control-label">Item</label>
                <select asp-for="ItemId" id="item_select" class="form-control"></select>
            </div>
            <div class="form-group">
                <label asp-for="ShippingDate" class="control-label"></label>
                <input asp-for="ShippingDate" type="date" class="form-control" />
                <span asp-validation-for="ShippingDate" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="DeliveryDate" class="control-label"></label>
                <input asp-for="DeliveryDate" type="date" class="form-control" required="required"/>
                <span asp-validation-for="DeliveryDate" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="Qty" class="control-label"></label>
                <input asp-for="Qty" type="number" class="form-control" required="required" />
                <span asp-validation-for="Qty" class="text-danger"></span>
            </div>
            <div class="form-group">
                <label asp-for="Tracking" class="control-label"></label>
                <input asp-for="Tracking" class="form-control" />
                <span asp-validation-for="Tracking" class="text-danger"></span>
            </div>
            <div class="form-group">

                <label asp-for="Arrived" class="control-label"></label>
                <select name="Arrived" class="form-control">
                    <option value="N" selected>undelivered</option>
                    <option value="Y">arrived</option>
                </select>
            </div>
            <div class="form-group">
                <label asp-for="CaseClosed" class="control-label"></label>
                <select name="CaseClosed" class="form-control">
                    <option value="" selected>no case or case is open</option>
                    <option value="Y">closed by ebay</option>
                </select>
            </div>
            <div class="form-group">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </form>
    </div>
</div>

<div>
    <a asp-action="Index">Back to List</a>
</div>

@section Scripts {
    @{await Html.RenderPartialAsync("_ValidationScriptsPartial");}
}

---------------------------------------------------------------------

delivery view Edit.cshtml

@model ebay_track.Models.Delivery

@{

    ViewData["Title"] = "Edit";

}

<script src="~/lib/jquery/dist/jquery.js"></script>

<script type="text/javascript">

    $(document).ready(function () {

        $('#arrived_tag').append(

            $('<option>', { value: 'N', text: 'undelivered' }),

            $('<option>', { value: 'Y', text: 'arrived' })

        );

        if ('@Model.Arrived' == 'Y') {

            $('#arrived_tag option[value=Y]').prop('selected', true);

        }

        else {

            $('#arrived_tag option[value=N]').prop('selected', true);

        }

        $('#case_closed_tag').append(

            $('<option>', { value: '', text: 'no case or case is open' }),

            $('<option>', { value: 'Y', text: 'closed by ebay' })

        );

        if ('@Model.CaseClosed' == 'Y') {

            $('#case_closed_tag option[value=Y]').prop('selected', true);

        }

        

    });

</script>

<h2>Edit</h2>

<h4>Delivery</h4>

<hr />

<div class="row">

    <div class="col-md-4">

        <form asp-action="Edit">

            <div asp-validation-summary="ModelOnly" class="text-danger"></div>

            <input type="hidden" asp-for="Id" />

            <div class="form-group">

                <label asp-for="ItemId" class="control-label"></label>

                <select asp-for="ItemId" class="form-control" asp-items="ViewBag.ItemId"></select>

                <span asp-validation-for="ItemId" class="text-danger"></span>

            </div>

            <div class="form-group">

                <label asp-for="ShippingDate" class="control-label"></label>

                <input asp-for="ShippingDate" type="date" class="form-control" />

                <span asp-validation-for="ShippingDate" class="text-danger"></span>

            </div>

            <div class="form-group">

                <label asp-for="DeliveryDate" class="control-label"></label>

                <input asp-for="DeliveryDate" type="date" class="form-control" required="required"/>

                <span asp-validation-for="DeliveryDate" class="text-danger"></span>

            </div>

            <div class="form-group">

                <label asp-for="Qty" class="control-label"></label>

                <input asp-for="Qty" type="number" class="form-control" required="required" />

                <span asp-validation-for="Qty" class="text-danger"></span>

            </div>

            <div class="form-group">

                <label asp-for="Tracking" class="control-label"></label>

                <input asp-for="Tracking" class="form-control" />

                <span asp-validation-for="Tracking" class="text-danger"></span>

            </div>

            <div class="form-group">

                <label asp-for="Arrived" class="control-label"></label>

                <select name="Arrived" id="arrived_tag" class="form-control"></select>

            </div>

            <div class="form-group">

                <label asp-for="CaseClosed" class="control-label"></label>

                <select name="CaseClosed" id="case_closed_tag" class="form-control"></select>

            </div>

            <div class="form-group">

                <input type="submit" value="Save" class="btn btn-default" />

            </div>

        </form>

    </div>

</div>

<div>

    <a asp-action="Index">Back to List</a>

</div>

@section Scripts {

    @{await Html.RenderPartialAsync("_ValidationScriptsPartial");}

}

----------------------------------------------------------------------------------
start up.cs

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

namespace ebay_track
{
    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.AddDistributedMemoryCache(); // Adds a default in-memory implementation of IDistributedCache
            services.AddSession();

            var cs = Configuration.GetConnectionString("ebayConnection");
            services.AddDbContext<ebayContext>(options => options.UseSqlServer(cs));
        }

        // 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();

            // IMPORTANT: This session call MUST go before UseMvc()
            app.UseSession();

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

----------------------------------------------------------------------------------
sql querry

create table item
(
id int IDENTITY(1,1) PRIMARY KEY,
name char(50) not null
)

create table delivery
(
id int IDENTITY(1,1) PRIMARY KEY,
item_id int foreign key references item(id) not null,
date datetime not null,
tracking char(50),
arrived char(1) check (arrived in ('Y','N')) not null
)

select * from item;

select d.date, i.name, d.tracking, d.arrived from delivery as d
inner join item as i on d.item_id = i.id
where d.arrived = 'Y'
order by d.date;

reference:
https://www.codeproject.com/Tips/1158082/Date-Time-Picker-in-ASP-NET-Core-using-Jquery-Plug
https://msdn.microsoft.com/fr-fr/library/system.datetime.compare(v=vs.110).aspx
https://www.codeproject.com/Articles/758458/Passing-Data-View-to-Controller-Controller-to-View
https://www.w3schools.com/jsref/jsref_replace.asp
https://stackoverflow.com/questions/20510023/mvc-redirect-to-view-from-jquery-with-parameters
https://stackoverflow.com/questions/740195/adding-options-to-a-select-using-jquery
https://stackoverflow.com/questions/13343566/set-select-option-selected-by-value
https://stackoverflow.com/questions/2656576/select-top-5-in-entity-framework

sessions:
https://chuanshuoge2.blogspot.ca/2018/01/sessions-asp-core.html