基于.NET Core的跨平台开发，配置文件与之前.NET Framework采用xml的config文件不同，目前主要是采用json文件键值对配置方式读取。
参考网上相关资料总结如下：
一. 引入扩展 System.Configuration.ConfigurationManager
Nuget 下载扩展，Install-Package System.Configuration.ConfigurationManager
使用方式：添加配置文件App.config。读取方式与原.NET Framework方式一致
优点：兼容.NET Framework 原有配置方式
缺点：项目运行过程中若需修改App.config文件，对项目中输出的内容没有丝毫影响，Debug发现获取到的值的确没有变化，需要重新编译才生效。
二. 引入扩展 Microsoft.Extensions.Options.ConfigurationExtensions
Nuget 下载扩展，
Install-Package Microsoft.Extensions.Options.ConfigurationExtensions
Install-Package Microsoft.Extensions.Configuration.FileExtensions
Install-Package Microsoft.Extensions.Configuration.Json
优点：可以读取application.json中的配置参数，不再使用XML可以说很好的贴近Core的设计理念
缺点：运行时修改json文件读取到的内容不会改变，但是至少重启项目可以修改，若要运行时候修改json文件监听实现监听变化。查看源码，可以发现 虽然配置信息是通过AddSingleton注入的
但同时也注入了IOptionsChangeTokenSource ，故只需要在获取配置信息时将IOptions<> 替换为 IOptionsMonitor<>(通过监听的Option来获取信息)，并通过 IOptionsMonitor<>.CurrentValue获取即可实时获取到最新的配置信息(存在修改监听)
另外就是，这个方法采用的是反序列化的原理，也就是必须有一个跟配置文件对应的实体类才可以，这个感觉比较鸡肋，放弃。
三. 自定义扩展方法，这个实现自己写，原理是监听文件是否变更，来刷新Configuration 配置实现。
参考园友一个实现，具体需要是否有效，要花时间实践一下，原链接地址：http://www.cnblogs.com/kasimlz/p/7515810.html，代码如下：
public class ConfigurationManager { /// <summary> /// 配置内容 /// </summary> private static NameValueCollection _configurationCollection = new NameValueCollection(); /// <summary> /// 配置监听响应链堆栈 /// </summary> private static Stack<KeyValuePair<string, FileSystemWatcher>> FileListeners = new Stack<KeyValuePair<string, FileSystemWatcher>>(); /// <summary> /// 默认路径 /// </summary> private static string _defaultPath = Directory.GetCurrentDirectory() + "\\appsettings.json"; /// <summary> /// 最终配置文件路径 /// </summary> private static string _configPath = null; /// <summary> /// 配置节点关键字 /// </summary> private static string _configSection = "AppSettings"; /// <summary> /// 配置外连接的后缀 /// </summary> private static string _configUrlPostfix = "Url"; /// <summary> /// 最终修改时间戳 /// </summary> private static long _timeStamp = 0L; /// <summary> /// 配置外链关键词，例如：AppSettings.Url /// </summary> private static string _configUrlSection { get { return _configSection + "." + _configUrlPostfix; } } static ConfigurationManager() { ConfigFinder(_defaultPath); } /// <summary> /// 确定配置文件路径 /// </summary> private static void ConfigFinder(string Path) { _configPath = Path; JObject config_json = new JObject(); while (config_json != null) { config_json = null; FileInfo config_info = new FileInfo(_configPath); if (!config_info.Exists) break; FileListeners.Push(CreateListener(config_info)); config_json = LoadJsonFile(_configPath); if (config_json[_configUrlSection] != null) _configPath = config_json[_configUrlSection].ToString(); else break; } if (config_json == null || config_json[_configSection] == null) return; LoadConfiguration(); } /// <summary> /// 读取配置文件内容 /// </summary> private static void LoadConfiguration() { FileInfo config = new FileInfo(_configPath); var configColltion = new NameValueCollection(); JObject config_object = LoadJsonFile(_configPath); if (config_object == null || !(config_object is JObject)) return; if (config_object[_configSection]!=null) { foreach (JProperty prop in config_object[_configSection]) { configColltion[prop.Name] = prop.Value.ToString(); } } _configurationCollection = configColltion; } /// <summary> /// 解析Json文件 /// </summary> /// <param name="FilePath">文件路径</param> /// <returns></returns> private static JObject LoadJsonFile(string FilePath) { JObject config_object = null; try { StreamReader sr = new StreamReader(FilePath, Encoding.Default); config_object = JObject.Parse(sr.ReadToEnd()); sr.Close(); } catch { } return config_object; } /// <summary> /// 添加监听树节点 /// </summary> /// <param name="info"></param> /// <returns></returns> private static KeyValuePair<string, FileSystemWatcher> CreateListener(FileInfo info) { FileSystemWatcher watcher = new FileSystemWatcher(); watcher.BeginInit(); watcher.Path = info.DirectoryName; watcher.Filter = info.Name; watcher.IncludeSubdirectories = false; watcher.EnableRaisingEvents = true; watcher.NotifyFilter = NotifyFilters.Attributes | NotifyFilters.CreationTime | NotifyFilters.DirectoryName | NotifyFilters.FileName | NotifyFilters.LastAccess | NotifyFilters.LastWrite | NotifyFilters.Size; watcher.Changed += new FileSystemEventHandler(ConfigChangeListener); watcher.EndInit(); return new KeyValuePair<string, FileSystemWatcher>(info.FullName, watcher); } private static void ConfigChangeListener(object sender, FileSystemEventArgs e) { long time = TimeStamp(); lock (FileListeners) { if (time > _timeStamp) { _timeStamp = time; if (e.FullPath != _configPath || e.FullPath == _defaultPath) { while (FileListeners.Count > 0) { var listener = FileListeners.Pop(); listener.Value.Dispose(); if (listener.Key == e.FullPath) break; } ConfigFinder(e.FullPath); } else { LoadConfiguration(); } } } } private static long TimeStamp() { return (long)((DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).TotalMilliseconds * 100); } private static string c_configSection = null; public static string ConfigSection { get { return _configSection; } set { c_configSection = value; } } private static string c_configUrlPostfix = null; public static string ConfigUrlPostfix { get { return _configUrlPostfix; } set { c_configUrlPostfix = value; } } private static string c_defaultPath = null; public static string DefaultPath { get { return _defaultPath; } set { c_defaultPath = value; } } public static NameValueCollection AppSettings { get { return _configurationCollection; } } /// <summary> /// 手动刷新配置，修改配置后，请手动调用此方法，以便更新配置参数 /// </summary> public static void RefreshConfiguration() { lock (FileListeners) { //修改配置 if (c_configSection != null) { _configSection = c_configSection; c_configSection = null; } if (c_configUrlPostfix != null) { _configUrlPostfix = c_configUrlPostfix; c_configUrlPostfix = null; } if (c_defaultPath != null) { _defaultPath = c_defaultPath; c_defaultPath = null; } //释放掉全部监听响应链 while (FileListeners.Count > 0) FileListeners.Pop().Value.Dispose(); ConfigFinder(_defaultPath); } } }