Error CS1061 'DbContextOptionsBuilder' does not contain a definition > for 'UseSqlServer' and no extension method 'UseSqlServer'

Question

Not sure which assembly I should reference to, to remove this blocking error.

public void ConfigureServices(IServiceCollection services)
{
    // Add framework services.
    services.AddDbContext<QAContext>(options => options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));
    // Add framework services.
    services.AddMvc();
}

Error CS1061 '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?)

Answer 1

If you are using EntityFrameworkCore you must:

Add to Reference:

Microsoft.EntityFrameworkCore.SqlServer

Add to source file:

using Microsoft.EntityFrameworkCore;

Answer 2

First go to toolbar > Tools > NuGet Package Manager > Package Manager Console, And it will be open below type "Install-Package Microsoft.EntityFrameworkCore.SqlServer" and it will solved.