.NET CORE 获取配置文件信息

.NET CORE 获取配置文件信息

动态获取appsettings.json文件里的配置信息

public class AppSetting
    {
        private static readonly object objLock = new object();
        private static AppSetting instance = null;

        private IConfigurationRoot Config { get; }

        private AppSetting()
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(Directory.GetCurrentDirectory())
                .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true);
            Config = builder.Build();
        }

        public static AppSetting GetInstance()
        {
            if (instance == null)
            {
                lock (objLock)
                {
                    if (instance == null)
                    {
                        instance = new AppSetting();
                    }
                }
            }

            return instance;
        }

        public static string GetConfig(string name)
        {
            return GetInstance().Config.GetSection(name).Value;
        }
    }

注意：在类库里写这个代码时会提示ConfigurationBuilder缺少引用，或者找不到SetBasePath方法，这时你需要引用以下NuGet包：
Microsoft.Extensions.Configuration
Microsoft.Extensions.Configuration.FileExtensions
Microsoft.Extensions.Configuration.Json