ASP.NET Core - Setup Entity Framework

In this chapter, we will set up and configure our application to save and read data from a SQL Server database.

To work with a database, we are going to use the Entity Framework, which is freshly rewritten to work with the new .NET Framework. If you have worked with EF in the past, you will see many familiar pieces.

  • In this application, we will use the SQL Server LocalDB. If you are not comfortable with the SQL Server, you can use any database that you like such as local database, remote database, as long as you have permission to create a new database on the instance.

  • LocalDB is a special edition of SQL Server that is optimized for developers.

  • Visual Studio 2015 and even its Community edition will install LocalDB by default.

To check the LocalDB, go to the View → SQL Server Object Explorer menu option in Visual Studio.

View SQL Server Object Explorer

This is a great tool if you have to work with SQL Server because it allows you to explore databases and browse data and even create data inside a database. When you first open it, it might take a little time, but it should connect to the LocalDB automatically.

Install Entity Framework

The first step in using the Entity Framework is to install the Entity Framework NuGet package from the NuGet package manager or by editing the project.json file directly.

Let us now edit the project.json file directly by adding the following two packages.

Project Json

The EntityFramework.Commands package helps us perform tasks with the Entity Framework like creating a database schema based on our C# Entity classes and these tasks are available from a command line tool where the logic lives inside the EntityFramework.Commands package.

In order to use this command line tool, we need to make an additional entry into the commands section of project.json as shown in the following screenshot.

Command Line Tool

We have just called it “ef” and that will map to this EntityFramework.Commands package. We can use this “ef” to get access to some of the logic that is available inside EntityFramework.Commands.

The following is the implementation of the project.json file.

{ 
   "version": "1.0.0-*", 
   "compilationOptions": { 
      "emitEntryPoint": true 
   },  
   
   "dependencies": { 
      "Microsoft.AspNet.Mvc": "6.0.0-rc1-final", 
      "Microsoft.AspNet.Diagnostics": "1.0.0-rc1-final", 
      "Microsoft.AspNet.IISPlatformHandler": "1.0.0-rc1-final", 
      "Microsoft.AspNet.Server.Kestrel": "1.0.0-rc1-final", 
      "Microsoft.AspNet.StaticFiles": "1.0.0-rc1-final", 
      "EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final", 
      "EntityFramework.Commands": "7.0.0-rc1-final" 
   }
   
   "commands": { 
      "web": "Microsoft.AspNet.Server.Kestrel" 
   },  
  
   "frameworks": { 
      "dnx451": { }, 
      "dnxcore50": { } 
   },  
  
   "exclude": [ 
      "wwwroot", 
      "node_modules" 
   ], 
  
   "publishExclude": [ 
      "**.user", 
      "**.vspscc" 
   ] 
}
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