Can't read appsettings.json without DI due to missing Configuration Builder

Question

I'm trying to read from appsettings.json and I don't want to use DI. I simply wish to access the file. I'm following simple configuration as suggested by MS.

using System.IO;
using Microsoft.Extensions.Configuration;

class Program
{
  public static IConfigurationRoot Configuration { get; set; }

  static void Main(string[] args)
  {
    IConfigurationBuilder builder = new ConfigurationBuilder()
      .SetBasePath(Directory.GetCurrentDirectory())
      .AddJsonFile("appsettings.json");

    Configuration = builder.Build();
  }
}

The classes get from red highlight to green when I specify the reference to Microsoft.Extensions.Configuration except for one - the Configuration Builder instance creation. It produces the following error.

Error CS0246 The type or namespace name 'ConfigurationBuilder' could not be found (are you missing a using directive or an assembly reference?)

All the examples I've found are set up the same way. Even the docs for Configuration Builder say that it's supopsed to be there. I'm at a loss on how to proceed.

I'm using .NET Core 2.0 if it's of any significance.

Answer 1

AddJsonFile method is in the Microsoft.Extensions.Configuration.Json package and in the Microsoft.Extensions.Configuration namespace.

So Microsoft.Extensions.Configuration.Json package need to be added to project.Once all the packages are restored successfully it works perfectly. If you have already added them another error might be blocking the build before that point gets compiled.

Answer 2

I had something similar. I already had ConfigurationBuilder referenced and working in another project of the same solution.

I copy/pasted the ConfigurationBuilder code to a new project and got the same problem as you.

I looked at NuGet installed packages for the solution.

Sure enough, Microsoft.Extensions.Configuration.Json was installed for the working project but not the new one.

Installed it for the new project and voilà.