ASP.NET Core Dependency Injection

Question

In my asp.net core solution I have 2 projects: asp.net app and library with model layer which contains pattern repository.

I ask DI in app realize my interface

services.AddTransient<IRepositrory, Repository>();

But! Repository constructor has parameter

public Repository(string connectionString)
{
    _appDBContext = new AppDBContext(connectionString);
}

How correctly configure DI to create repository with specific string from appsettings.json (asp.net app)?

Your repository class should get AppDbContext injected as a dependency. What you have now is not proper DI design — MikeSW
– MikeSW, Commented Jul 8, 2016 at 18:09
public Repository(IDBContext dbContext) something like this? — Nikishkin Sergey
– Nikishkin Sergey, Commented Jul 8, 2016 at 20:26

krontogiannis · Accepted Answer · 2016-07-08 17:56:37Z

4

There is an overload that accepts an implementation factory

services.AddTransient<IRepository>(isp => new Repository(conn));

You can get the connection string using

Configuration.GetConnectionString("DefaultConnection")

answered Jul 8, 2016 at 17:56

krontogiannis

1,9391 gold badge14 silver badges19 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

ocuenca · Accepted Answer · 2016-07-08 18:20:54Z

3

You can also use AddInstance method:

var connectionString=Configuration.GetConnectionString("DefaultConnection");
services.AddInstance<IRepository>(new Repository(connectionString));

But I'm agree with @MikeSW what he said in his comment above. You should register your DbContext and use it as parameter in your repository constructor:

 services.AddDbContext<AppDBContext>(options =>
        options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

And your constructor would be:

public Repository(AppDBContext context)
{
    _appDBContext = context;
}

edited Jul 8, 2016 at 18:20

answered Jul 8, 2016 at 18:06

ocuenca

39.5k12 gold badges95 silver badges107 bronze badges

Comments

Kixoka · Accepted Answer · 2016-07-08 18:17:20Z

you should be putting the services in ConfigureServices method of Startup.cs

    public Startup()
    {
        var builder = new ConfigurationBuilder()
                        .AddJsonFile("appsettings.json");
        Configuration = builder.Build();
    }

    public IConfiguration Configuration { get; set; }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc();

        services.AddEntityFramework()
                .AddSqlServer()
                .AddDbContext<MyDbContext>(
            options => options.UseSqlServer(Configuration["database:connection"]));
     }

Where appsettings.json:

{
"database": {
"connection":  "Data Source=(localdb)\\mssqllocaldb;Initial Catalog=MyDb"
   }
 }

Jani Devang · Accepted Answer · 2016-11-07 18:14:16Z

0

services.AddTransient<IRepository>(isp => new Repository(connection));

Use this for accepts an implementation factory and to retrieve connection string use this:-

Configuration.GetConnectionString("DefaultConnection")

answered Nov 7, 2016 at 18:14

Jani Devang

1,10913 silver badges20 bronze badges

Collectives™ on Stack Overflow

ASP.NET Core Dependency Injection

4 Answers 4

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related