Efcore: VS 2017 shows red squiggly on UseSqlSever when method is resolved

[Rick-Anderson]

To reproduce:

1. Create new ASP.NET Core web app with all defaults.
2. Add Movie class

public class Movie
    {
        public int ID { get; set; }
        public string Title { get; set; }
        public DateTime ReleaseDate { get; set; }
        public string Genre { get; set; }
        public decimal Price { get; set; }
    }  

3.Scaffold

1. Build/run - it works fine.
2. Open _Startup.cs_ and UseSqlSever is underlined with red squiggly. It shows the error:
   'DbContextOptionsBuilder' does not contain a definition for 'UseSqlServer' and no extension method 'UseSqlServer' accepting a first argument of type 'DbContextOptionsBuilder' could be found (are you missing a using directive or an assembly reference?)

[hernanbignone]

Still happend

[Rick-Anderson]

@hernanbignone see https://github.com/aspnet/EntityFramework/issues/7891

[mukeshrebari]

it worked by installing package Microsoft.EntityFrameworkCore.Sqlite.Core

[wpqs]

I need to use SQLServer, not SQLite so added package Microsoft.EntityFrameworkCore.SqlServer

[davkean]

This is likely because you've not got the package installed, https://github.com/aspnet/EntityFrameworkCore/issues/7891#issuecomment-401540512.

[shepherdnick]

Open your console and navigate to the project folder, then run this:

dotnet add package Microsoft.EntityFrameworkCore.Sqlite

You'll need to then add a using Microsoft.EntityFrameworkCore.Sqlite to the top of your class.

See here: https://docs.microsoft.com/en-us/ef/core/get-started/netcore/new-db-sqlite

[alirezaseif28]

yes.ok

[ollypapi]

You gonna need to install some nugget, create a table and do db-migration

[StuartMc77]

Open your console and navigate to the project folder, then run this:

dotnet add package Microsoft.EntityFrameworkCore.Sqlite

You'll need to then add a using Microsoft.EntityFrameworkCore.Sqlite to the top of your class.

See here: https://docs.microsoft.com/en-us/ef/core/get-started/netcore/new-db-sqlite

Thank you... this worked for me after I've updated my app from core 2.1 to 3.1 it must've removed that using reference. So easy to miss.

[TRUSTVIEWIO]

I don't get it.

why all this..

Just add
using Microsoft.EntityFrameworkCore;

Just read the library before using it... why nobody does that..

[jspalding70]

I am doing tutorial now which gave same issue until I added
Install-Package Microsoft.EntityFrameworkCore.InMemory

[TRUSTVIEWIO]

I am doing tutorial now which gave same issue until I added
Install-Package Microsoft.EntityFrameworkCore.InMemory

why do you need Microsoft.EntityFrameworkCore.InMemory

To do UseSqlServer call

Which is static function in Microsoft.EntityFrameworkCore(Microsoft.EntityFrameworkCore.SqlServer.dll)

//
// Summary:
// Configures the context to connect to a Microsoft SQL Server database.
//
// Parameters:
// optionsBuilder:
// The builder being used to configure the context.
//
// connectionString:
// The connection string of the database to connect to.
//
// sqlServerOptionsAction:
// An optional action to allow additional SQL Server specific configuration.
//
// Returns:
// The options builder so that further configuration can be chained.
public static DbContextOptionsBuilder UseSqlServer([NotNullAttribute] this DbContextOptionsBuilder optionsBuilder, [NotNullAttribute] string connectionString, [CanBeNullAttribute] Action sqlServerOptionsAction = null);
//
// Summary:
// Configures the context to connect to a Microsoft SQL Server database.
//
// Parameters:
// optionsBuilder:
// The builder being used to configure the context.
//
// connection:
// An existing System.Data.Common.DbConnection to be used to connect to the database.
// If the connection is in the open state then EF will not open or close the connection.
// If the connection is in the closed state then EF will open and close the connection
// as needed.
//
// sqlServerOptionsAction:
// An optional action to allow additional SQL Server specific configuration.
//
// Returns:
// The options builder so that further configuration can be chained.
public static DbContextOptionsBuilder UseSqlServer([NotNullAttribute] this DbContextOptionsBuilder optionsBuilder, [NotNullAttribute] DbConnection connection, [CanBeNullAttribute] Action sqlServerOptionsAction = null);

[Rick-Anderson]

@jspalding70

I am doing tutorial now which gave same issue until I added Install-Package Microsoft.EntityFrameworkCore.InMemory

That's in the tutorial.

[TRUSTVIEWIO]

@jspalding70

I am doing tutorial now which gave same issue until I added Install-Package Microsoft.EntityFrameworkCore.InMemory

That's in the tutorial.

Oka so you use SQLite

This topic its about MS SQL and EFCore..

When i work with EFCore
I use Microsoft.EntityFrameworkCore.SqlServer.dll and Microsoft.EntityFrameworkCore.Proxies.dll
use of UseLazyLoadingProxies

Microsoft.EntityFrameworkCore.Sqlite better to use with Microsoft.EntityFrameworkCore.Proxies then Microsoft.EntityFrameworkCore.InMemory

CPU lower cost..

[sundardsTechMind]

Step 1: Right click your project
Step 2: Manage NuGet Package
Step 3. Browse tab
Step 4. Search ( Microsoft.EntityFrameworkCore.SqlServer )
Step 5. Install
Step 6. build
Step 7. Success................................................................

added package Microsoft.EntityFrameworkCore.SqlServer

[JacksReacher]

I think the confusion is that people are trying this out for the first time and the little blue checkmark is confusing them into thinking the package is already installed.... not very good UI design IMHO

[marcotargino]

Step 1: Right click your project
Step 2: Manage NuGet Package
Step 3. Browse tab
Step 4. Search ( Microsoft.EntityFrameworkCore.SqlServer )
Step 5. Install
Step 6. build
Step 7. Success................................................................

added package Microsoft.EntityFrameworkCore.SqlServer

Dude, u saved me!!! Thanks bro! God bless ya

[kmkrish007]

After installing Microsoft.EntityFrameworkCore.SqlServer Nuget package my issue resolved.