讀取其他 app.config 檔

參考引用:AppSettings get value from .config file
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'設定其他 .config 檔
AppDomain.CurrentDomain.SetData("APP_CONFIG_FILE", @"d:\test\justAConfigFile.config.whateverYouLikeExtension");
ConfigurationManager.RefreshSection("appSettings");

string value = ConfigurationManager.AppSettings["NewKey0"];