.NET Core读取配置文件

public static class MengTConfig
    {
        static IConfigurationRoot _MT_Configuration { get; }
        static IConfigurationSection _MT_AppSetting;
        static MengTConfig()
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(AppContext.BaseDirectory)
                .AddJsonFile("_config/MengT.json", optional: true, reloadOnChange: true);

            _MT_Configuration = builder.Build();

            _MT_AppSetting = _MT_Configuration.GetSection("AppSettings");

        }
        /// <summary>
        /// 通过[Key]获取数据库连接字符串
        /// </summary>
        /// <param name="_key">Key</param>
        /// <returns></returns>
        public static string GetConnectionString(string _key)
        {
            return _MT_Configuration.GetConnectionString(_key);
        }

        /// <summary>
        /// 通过[Key]获取配置信息
        /// </summary>
        /// <param name="_key">Key</param>
        /// <returns></returns>
        public static string GetAppSetting(string _key)
        {
            return _MT_AppSetting[_key];
        }
    }