{
 "name": "wen",
 "age": 26,
 "family": {
 "mother": {
  "name": "娘",
  "age": 55
 },
 "father": {
  "name": "爹",
  "age": 56
 }
 }
}

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

namespace Demo
{
 class Program
 {
  static void Main(string[] args)
  {
   //添加 json 文件路径
   var builder = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory()).AddJsonFile("appsettings.json");
   //创建配置根对象
   var configurationRoot = builder.Build();

   //取配置根下的 name 部分
   var nameSection = configurationRoot.GetSection("name");
   //取配置根下的 family 部分
   var familySection = configurationRoot.GetSection("family");
   //取 family 部分下的 mother 部分下的 name 部分
   var motherNameSection = familySection.GetSection("mother").GetSection("name");
   //取 family 部分下的 father 部分下的 age 部分
   var fatherAgeSection = familySection.GetSection("father").GetSection("age");

   //Value 为文本值
   Console.WriteLine($"name: {nameSection.Value}");
   Console.WriteLine($"motherName: {motherNameSection.Value}");
   Console.WriteLine($"fatherAge: {fatherAgeSection.Value}");
   Console.Read();
  }
 }
}