ASP.NET Core: JSON Configuration GetSection returns null

Question

I have a file appsettings.json that looks like this:

{
    "MyConfig": {
        "ConfigA": "value",
        "ConfigB": "value"
    }
}

In my Startup.cs I'm building my IConfiguration:

public ConfigurationRoot Configuration { get; set; }

public Startup(ILoggerFactory loggerFactory, IHostingEnvironment environment)
{
      var builder = new ConfigurationBuilder()
                     .SetBasePath(environment.ContentRootPath)
                     .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)                             
                     .AddEnvironmentVariables();

      Configuration = builder.Build();
}

public void ConfigureServices(IServiceCollection services)
{
      //GetSection returns null...
      services.Configure<MyConfig>(Configuration.GetSection("MyConfig"));
}

But Configuration.GetSection("MyConfig") always returns null, although the value exists in my JSON file. Configuration.GetSection("MyConfig:ConfigA") works just fine.

What am I doing wrong?

Could this be the issue for you too? stackoverflow.com/questions/50669724/… — Rajiv
– Rajiv, Commented Aug 3, 2018 at 13:10

coryrwest · Accepted Answer · 2019-04-10 15:32:16Z

20

For anyone who happens upon this and is trying to do this same thing in a test project, this is what worked for me:

other = config.GetSection("OtherSettings").Get<OtherSettings>();

answered Apr 10, 2019 at 15:32

coryrwest

7191 gold badge8 silver badges23 bronze badges

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

1 Comment

oatsoda Over a year ago

This is useful for startup too - where you don't want to Configure because you need the settings for registering within DI, never within a resolved dependency.

Herman · Accepted Answer · 2018-05-25 09:28:30Z

5

Please refer to this below code

public class Startup
{
    public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        var config = Configuration.GetSection("MyConfig");
        // To get the value configA
        var value = config["ConfigA"];

        // or direct get the value
        var configA = Configuration.GetSection("MyConfig:ConfigA");

        var myConfig = new MyConfig();
        // This is to bind to your object
        Configuration.GetSection("MyConfig").Bind(myConfig);
        var value2 = myConfig.ConfigA;
    }
}

answered May 25, 2018 at 9:28

Herman

3,0287 gold badges30 silver badges40 bronze badges

2 Comments

Dan Friedman Over a year ago

Refer to what in the code? All I see is a different way to do the same thing.

oleksa Over a year ago

@DanFriedman i've just found this question trying to solve the same GetSection().Value is null. To get value I've used GetSection("sectionName").Bind(myConfig) like in the code above and has got myConfig instance properties were populated with configuration section sectionName values

Alex-v-s · Accepted Answer · 2020-08-06 00:52:59Z

4

I just ran into this. The values are there if you use the full path, but I needed to auto-bind them to a configuration class.

The .Bind(config) started working after I added auto-property accessors to my class's properties. i.e.

public class MyAppConfig {
  public string MyConfigProperty { get; set;} //this works
  public string MyConfigProperty2; //this does not work
}

edited Aug 6, 2020 at 0:52

answered Apr 4, 2019 at 22:19

Alex-v-s

1871 silver badge14 bronze badges

Comments

Robert · Accepted Answer · 2018-11-15 11:52:20Z

1

This worked for me.

public void ConfigureServices(IServiceCollection services)  
{  
     services.Configure<MyConfig>(con=> Configuration.GetSection("MyConfig").Bind(con));  
}

edited Nov 15, 2018 at 11:52

Robert

5,31843 gold badges70 silver badges115 bronze badges

answered Nov 15, 2018 at 11:30

Isuru Amarathunga

2,4371 gold badge22 silver badges20 bronze badges

Comments

Peter Csala · Accepted Answer · 2021-12-27 05:17:07Z

1

I am used to use fields instead of properties on my classes and i faced the same issue than you...

Turns out that they need to be properties, otherwise it doesn't complete the values of the class but leaves them as default.

Based on this MSDN article an options class:

Must be non-abstract with a public parameterless constructor.

All public read-write properties of the type are bound.

Fields are not bound. In the preceding code, Position is not bound. The Position property is used so the string "Position" doesn't need to be hard coded in the app when binding the class to a configuration provider.

edited Dec 27, 2021 at 5:17

Peter Csala

23.7k16 gold badges51 silver badges96 bronze badges

answered Dec 27, 2021 at 2:59

Ezequiel M

111 bronze badge

Comments

apaksoy · Accepted Answer · 2023-08-17 13:12:57Z

0

I had the same problem. I checked the Configuration object on host builder context. It was looking for the appsettings.json in a different directory, e.g., something like "MyRootDirectory\publish" instead of "MyRootDirectory". This in turn was beacuse somehow my debug profile's working directory was set to "MyRootDirectory\publish".

I deleted "\publish" from working directory setting of my projects debug profile and the problem was resolved.

You can find your project's working directory in debug mode by right clicking on your project and navigating to Properties -> Debug -> General.

edited Aug 17, 2023 at 13:12

answered Aug 17, 2023 at 13:11

apaksoy

12 bronze badges

Collectives™ on Stack Overflow

ASP.NET Core: JSON Configuration GetSection returns null

6 Answers 6

1 Comment

2 Comments

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

1 Comment

2 Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related