为什么 SetBasePath 在 .NET Core 3.1 中不起作用？ 我试过添加 nuget 包，但它不起作用

Question

Error CS1061
'ConfigurationBuilder' does not contain a definition for 'SetBasePath' and no accessible extension method 'SetBasePath' accepting a first argument of type 'ConfigurationBuilder' could be found (are you missing a using directive or an assembly reference?)

screenshot

I've installed these packages:

Microsoft.Extensions.Configuration;
Microsoft.Extensions.Configuration.Json;
Microsoft.Extensions.Configuration.FileExtensions

The code is working in .NET Core 2.2 but not in .NET Core 3.1.

Code is here:

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

namespace Core.Logic.Mappers
{
    public class MappingProfile : Profile
    {
        public MappingProfile()
        {
            IConfigurationRoot configuration = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory())
                                                                         .AddJsonFile("appsettings.json")
                                                                         .Build();

Answer 1

Finally, after couple days I found solution:

I have multiple-projects in my solution, so I was installing

    Microsoft.Extensions.Configuration.Json;

to other project. Noobie :D