Connect to database using . Net Core 2

Question

I am studying . Net Core 2 and I am unable to make the connection to the database.

My appsettings.json looks like this:

"ConnectionStrings": {
     "DefaultConnection": "Server=FAYOL\\SQLEXPRESS;Database=Pagamento;Trusted_Connection=True;MultipleActiveResultSets=true"
},

And the Startup.Cs

using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using Repository; 
namespace Radix
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();

        var connection = @"Server=FAYOL\SQLEXPRESS;Database=Pagamento;Trusted_Connection=True;ConnectRetryCount=0";
        services.AddDbContext<Contexto>(options => options.UseSqlServer(connection));
    }
}

}

I’m not sure how to point out the Startup.cs for Json and how to do this. I took an example on the internet q puts the string directly in the ConfigureServices (as the example above) and is giving error.

Can you help me?

Thank you

Answer 1

To recover the connection string from appsettings.json you can do it this way

using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration
using Microsoft.Extensions.DependencyInjection;
using Repository; 
namespace Radix
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }
        public IConfiguration Configuration { get; }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            string connecttionStringV2 = Configuration.GetSection("ConnectionStrings")["DefaultConnection"];
            string connectionString = Configuration.GetConnectionString("DefaultConnection");
            services.AddDbContext<Contexto>(options => options.UseSqlServer(connection));
        }
    }
}