.net core 读取 appsettings.json 值

namespace Utility
{
    public class ConfigurationHelper
    {
        //先 NuGet:Microsoft.Extensions.Configuration
        //ConfigurationHelper.Configure(builder.Configuration);//在入口注册（写在var app = builder.Build();）之前
        //获取值方法
        //var Serve = ConfigurationHelper.GetConfigValueByKey("AppSettings:Serve");
        //var AllowedHosts = ConfigurationHelper.GetConfigValueByKey("AllowedHosts");

        public static void Configure(IConfiguration config)
        {
           _configuration = config;
        }

        public static IConfiguration _configuration;
      
        public static string GetConfigValueByKey(string key)
        {
            return _configuration[key];
        }

    }
}