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ASP.NET (snapshot 2017) Microsoft documentation and samples

[!INCLUDEadding-model]

Note: The ASP.NET Core 2.0 templates contain the Models folder.

Right-click the Models folder > Add > Class. Name the class Movie and add the following properties:

[!code-csharpMain]

   1:  //#define MovieNoEF
   2:  #if MovieNoEF
   3:  #region snippet_1
   4:  using System;
   5:   
   6:  namespace MvcMovie.Models
   7:  {
   8:      public class Movie
   9:      {
  10:          public int ID { get; set; }
  11:          public string Title { get; set; }
  12:          public DateTime ReleaseDate { get; set; }
  13:          public string Genre { get; set; }
  14:          public decimal Price { get; set; }
  15:      }
  16:  }
  17:  #endregion
  18:  #endif

The ID field is required by the database for the primary key.

Build the project to verify you don’t have any errors. You now have a Model in your MVC app.

Scaffolding a controller

In Solution Explorer, right-click the Controllers folder > Add > Controller.

view of above step
view of above step

If the Add MVC Dependencies dialog appears:

In the Add Scaffold dialog, tap MVC Controller with views, using Entity Framework > Add.

Add Scaffold dialog
Add Scaffold dialog

Complete the Add Controller dialog:

Add Data context
Add Data context
Add Controller dialog
Add Controller dialog

Visual Studio creates:

The automatic creation of the database context and CRUD (create, read, update, and delete) action methods and views is known as scaffolding. You’ll soon have a fully functional web application that lets you manage a movie database.

If you run the app and click on the Mvc Movie link, you get an error similar to the following:

An unhandled exception occurred while processing the request.

SqlException: Cannot open database "MvcMovieContext-<GUID removed>" requested by the login. The login failed.
Login failed for user 'Rick'.

System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString 

You need to create the database, and you’ll use the EF Core (xref:)Migrations feature to do that. Migrations lets you create a database that matches your data model and update the database schema when your data model changes.

Add EF tooling and perform initial migration

In this section you’ll use the Package Manager Console (PMC) to:

From the Tools menu, select NuGet Package Manager > Package Manager Console.

PMC menu
PMC menu

In the PMC, enter the following commands:

Install-Package Microsoft.EntityFrameworkCore.Tools
Add-Migration Initial
Update-Database

Note: If you receive an error with the Install-Package command, open NuGet Package Manager and search for the Microsoft.EntityFrameworkCore.Tools package. This allows you to install the package or check if it is already installed. Alternatively, see the CLI approach if you have problems with the PMC.

The Add-Migration command creates code to create the initial database schema. The schema is based on the model specified in the DbContext(In the Data/MvcMovieContext.cs file). The Initial argument is used to name the migrations. You can use any name, but by convention you choose a name that describes the migration. See (xref:)Introduction to migrations for more information.

The Update-Database command runs the Up method in the *Migrations/<time-stamp>_Initial.cs* file, which creates the database.

You can perform the preceeding steps using the command-line interface (CLI) rather than the PMC:

[!INCLUDEadding-model]

[!code-csharpMain]

   1:  #if V1x
   2:  using System;
   3:  using System.Collections.Generic;
   4:  using System.Linq;
   5:  using System.Threading.Tasks;
   6:  using Microsoft.AspNetCore.Builder;
   7:  using Microsoft.AspNetCore.Hosting;
   8:  using Microsoft.Extensions.Configuration;
   9:  using Microsoft.Extensions.DependencyInjection;
  10:  using Microsoft.Extensions.Logging;
  11:  using Microsoft.EntityFrameworkCore;
  12:  using MvcMovie.Models;
  13:   
  14:  namespace MvcMovie
  15:  {
  16:      public class Startup
  17:      {
  18:          public Startup(IHostingEnvironment env)
  19:          {
  20:              var builder = new ConfigurationBuilder()
  21:                  .SetBasePath(env.ContentRootPath)
  22:                  .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
  23:                  .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
  24:                  .AddEnvironmentVariables();
  25:              Configuration = builder.Build();
  26:          }
  27:   
  28:          public IConfigurationRoot Configuration { get; }
  29:   
  30:          // This method gets called by the runtime. Use this method to add services to the container.
  31:          #region ConfigureServices
  32:          public void ConfigureServices(IServiceCollection services)
  33:          {
  34:              // Add framework services.
  35:              services.AddMvc();
  36:   
  37:              services.AddDbContext<MvcMovieContext>(options =>
  38:                      options.UseSqlServer(Configuration.GetConnectionString("MvcMovieContext")));
  39:          }
  40:          #endregion
  41:   
  42:   
  43:          // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
  44:          public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
  45:          {
  46:              loggerFactory.AddConsole(Configuration.GetSection("Logging"));
  47:              loggerFactory.AddDebug();
  48:   
  49:              if (env.IsDevelopment())
  50:              {
  51:                  app.UseDeveloperExceptionPage();
  52:   
  53:                  // Browser Link is not compatible with Kestrel 1.1.0
  54:                  // For details on enabling Browser Link, see https://go.microsoft.com/fwlink/?linkid=840936
  55:                  // app.UseBrowserLink();
  56:              }
  57:              else
  58:              {
  59:                  app.UseExceptionHandler("/Home/Error");
  60:              }
  61:   
  62:              #region snippet_seed
  63:              app.UseStaticFiles();
  64:              #region snippet_1
  65:              app.UseMvc(routes =>
  66:              {
  67:                  routes.MapRoute(
  68:                      name: "default",
  69:                      template: "{controller=Home}/{action=Index}/{id?}");
  70:              });
  71:              #endregion
  72:   
  73:              SeedData.Initialize(app.ApplicationServices);
  74:          }
  75:      }
  76:  }
  77:  #endregion
  78:  #endif

[!INCLUDEadding-model]

Intellisense contextual menu on a Model item listing the available properties for ID, Price, Release Date, and Title
Intellisense contextual menu on a Model item listing the available properties for ID, Price, Release Date, and Title

Additional resources

Previous Adding a View Next Working with SQL



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