前文讲获取配置文件内容的时候，是获取默认的appsettings.json配置文件的配置，下面说明下如何进行自定义配置文件获取

1. Json Provider

1.1 构建独立的IConfiguration

编写方法

        public static IConfigurationRoot LoadSettings(this IHostEnvironment env){return new ConfigurationBuilder().SetBasePath(AppDomain.CurrentDomain.BaseDirectory).AddJsonFile("common.json", optional: true, reloadOnChange: false).AddJsonFile("appsettings.json", optional: true, reloadOnChange: false).AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true, reloadOnChange: false).AddEnvironmentVariables().Build();}

在Startup构造函数的时候进行赋值替换IConfiguration

        private readonly IConfiguration _configuration;public Startup(IWebHostEnvironment env){_configuration = env.LoadSettings();}

该操作添加的配置项，只在startup范围生效。

1.2 在Progrom全局自定义配置

 public static IHostBuilder CreateHostBuilder(string[] args) =>Host.CreateDefaultBuilder(args).ConfigureAppConfiguration((hostingContext, config) =>{var env = hostingContext.HostingEnvironment;config.SetBasePath(env.ContentRootPath);config.AddJsonFile("devappsettings.json", optional: false, reloadOnChange: true);}).ConfigureWebHostDefaults(webBuilder =>{webBuilder.UseStartup<Startup>();});

注意：添加自定义文件的目录要注意，可能会存在因为目录问题所以找不到配置文件的情况。

2. Memory Provider

允许我们将一个应用程序配置直接配置到内存中，而不是像传统方式那样子必须制定一个物理文件。

            var builder = new ConfigurationBuilder();var profileCollection = new Dictionary<string, string>{{"AuthorProfile:FirstName", "Joydip"},{"AuthorProfile:LastName", "Kanjilal"},{"AuthorProfile:Address", "Hyderabad, India"}};builder.AddInMemoryCollection(profileCollection);Configuration = builder.Build();

使用

        public static IHostBuilder CreateHostBuilder(string[] args) =>Host.CreateDefaultBuilder(args).ConfigureAppConfiguration((hostingContext, config) =>{var builder = new ConfigurationBuilder();var profileCollection = new Dictionary<string, string>{{"AuthorProfile:FirstName", "Joydip"},{"AuthorProfile:LastName", "Kanjilal"},{"AuthorProfile:Address", "Hyderabad, India"}};builder.AddInMemoryCollection(profileCollection);config.AddConfiguration(builder.Build());}).ConfigureWebHostDefaults(webBuilder =>{webBuilder.UseStartup<Startup>();});

然后就可以通过IConfiguration实例去获取了。

3. 公共类获取配置文件

引用组件

Microsoft.Extensions.Configuration.Json

    public class AppSettings{private static IConfiguration Configuration { get; set; }public AppSettings(IConfiguration configuration){Configuration = configuration;}/// <summary>/// 封装要操作的字符/// </summary>/// <param name="ps"></param>/// <returns></returns>public static string GetValue(params string[] ps){try{if (ps.Any())return Configuration[string.Join(":", ps)];}catch (Exception){ }return "";}/// <summary>/// 递归获取配置信息数组///引用 Microsoft.Extensions.Configuration.Binder 包/// </summary>/// <typeparam name="T"></typeparam>/// <param name="ps"></param>/// <returns></returns>public static List<T> App<T>(params string[] ps){List<T> list = new List<T>();Configuration.Bind(string.Join(":", ps), list);return list;}}

参考自：https://gitee.com/laozhangIsPhi/Blog.Core

ConfigureServices中配置

services.AddSingleton(new AppSettings(Configuration));

获取指定配置

var info = AppSettings.GetValue("Logging", "LogLevel");