appsettings.json

{  "Logging": {    "LogLevel": {      "Default": "Information",      "Microsoft": "Warning",      "Microsoft.Hosting.Lifetime": "Information"
    }
  },  "option1": "Json",  "option2": 2,  //对象
  "subsection": {    "Id": 1,    "Name": "Max"
  },  //数组
  "wizards": 
    [
      {        "Name": "Gand",        "Age": "10"
      },
      {        "Name": "Harry",        "Age": "17"
      }
    ],  "AllowedHosts": "*"}

Startup.cs

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)//,ILoggerFactory factory        {            #region Asp.Net Core读取配置文件（JSON文件） 
            {                //xml path,不用区分大小写
                WriteLine($"option1 = {this.Configuration["option1"]}");
                WriteLine($"option2 = {this.Configuration["option2"]}");                //对象获取
                WriteLine($"subsection_Id = {this.Configuration["subsection:Id"]}");
                WriteLine($"subsection_Name = {this.Configuration["subsection:Name"]}");                //数组获取
                WriteLine("wizards");
                WriteLine($"wizardsFirst_Name = {this.Configuration["wizards:0:Name"]}");
                WriteLine($"wizardsFirst_Age = {this.Configuration["wizards:0:Age"]}");
                WriteLine($"wizardsSecond_Name = {this.Configuration["wizards:1:Name"]}");
                WriteLine($"wizardsSecond_Age = {this.Configuration["wizards:1:Age"]}");
            }            #endregion
            
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }            else
            {
                app.UseExceptionHandler("/Home/Error");
            }
            
            app.UseStaticFiles();
            app.UseSession();
            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Home}/{action=Index}/{id?}");
            });
        }