ExeConfigurationFileMap map = new ExeConfigurationFileMap();
            map.ExeConfigFilename = @"F:\App1.config"; ;
            Configuration config = ConfigurationManager.OpenMappedExeConfiguration(map, ConfigurationUserLevel.None);
            string connstr = config.ConnectionStrings.ConnectionStrings["connStr"].ConnectionString;
            MessageBox.Show(connstr);
            string key = config.AppSettings.Settings["key"].Value;
            MessageBox.Show(key);