读写配置节点appSettings```C# using System.Configuration; Configura


using System.Configuration;

Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
string strToken = config.AppSettings.Settings["NewMsgApiToken"].Value;//读取
config.AppSettings.Settings["NewMsgApiToken"].Value = strLastestToken;//写入
config.AppSettings.Settings.Add("test","testValue");//增加
config.AppSettings.Settings.Remove("tset");//删除
config.Save(ConfigurationSaveMode.Modified);//保存
ConfigurationManager.RefreshSection("appSettings");//刷新以生效