Pfthb

Every time I call Configuration.GetSection, the Value property of the returned object is always null.

My Startup constructor

public Startup(IHostingEnvironment env)

 var builder = new ConfigurationBuilder()
 .SetBasePath(env.ContentRootPath)
 .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
 .AddEnvironmentVariables();

 this.Configuration = builder.Build();

My ConfigureServices method

public void ConfigureServices(IServiceCollection services)

 services.Configure<SqliteSettings>(opts => Configuration.GetSection("SqliteSettings").Bind(opts));

 services.AddOptions();

 services.AddMvc();

My appsettings.json

 "SqliteSettings": 
 "DataSource": "C:\db.sqlite",
 "NewDatabase": true,
 "Version": 3
 

The class I'm using to define SqliteSettings

public class SqliteSettings

 public string DataSource get; set; 

 public bool? NewDatabase get; set; 

 public int? Version get; set; 

 public string Password get; set; 

 public long? CacheSize get; set; 

 // More properties

I was thinking the JSON might need to have the same amount of properties to match, or is it might be something to do with data type definitions, but maybe those are completely unrelated.

Just modify your ConfigureServices method to be like following

public void ConfigureServices(IServiceCollection services)

 services.AddOptions();

 services.Configure<SqliteSettings>(Configuration.GetSection("SqliteSettings"));

 services.AddMvc();

And it should work.

This worked for me in console application

var conncetionString = config["ConnectionStrings:DefaultConnection"]

var serviceProvider = services.BuildServiceProvider();

Must come after all services.Configure calls.

In my case for Web Api Core 2.1 I needed it in the project root folder. Same folder as Startup.cs, Program.cs.

If you have an appsettings.Development.json file, make sure the "ConnectionStrings:DefaultConnection" settings are in both appsettings.Development.json and appsettings.json files.

I had this problem before but my problem was that i put my json config file in wrong place ...
i should have put it in wwwroot folder . because asp.net core looks for files in this folder