ASP.NET Core DbContext injection

AddDbContext implementation just registers the context itself and its common dependencies in DI. Instead of AddDbContext call, it's perfectly legal to manually register your DbContext:

services.AddTransient<FooContext>();

Moreover, you could use a factory method to pass parameters (this is answering the question):

services.AddTransient<FooContext>(provider =>
{
    //resolve another classes from DI
    var anyOtherClass = provider.GetService<AnyOtherClass>();

    //pass any parameters
    return new FooContext(foo, bar);
});

P.S., In general, you don't have to register DbContextOptionsFactory and default DbContextOptions to resolve DbContext itself, but it could be necessary in specific cases.

You can use this in startup.cs.

Detail information : https://docs.microsoft.com/en-us/ef/core/miscellaneous/configuring-dbcontext

Detail Example : Getting started with ASP.NET Core MVC and Entity Framework Core

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

In order to register DbContext as a service in IServiceCollection you have two options:(we assume that you are going to connect to a SQL Server database)

Using AddDbContext<>

services.AddDbContext<YourDbContext>(o=>o.UseSqlServer(Your Connection String));

Using AddDbContextPool<>

services.AddDbContextPool<YourDbContext>(o=>o.UseSqlServer(Your Connection String));

as you might see these two are in terms of writing have similarities, but in fact they have some fundamental differences in terms of concepts. @GabrielLuci has a nice response about the differences between these two: https://stackoverflow.com/a/48444206/1666800

Also note that you can store your connection string inside the appsettings.json file and simply read it using: Configuration.GetConnectionString("DefaultConnection") inside the ConfigureServices method in Startup.cs file.