1. 读取某个文件夹下的Web.config中的appSection的节点,并修改保存
Configuration config = WebConfigurationManager.OpenWebConfiguration("~/rmsms");
AppSettingsSection appSection = (AppSettingsSection)config.GetSection("appSettings");
appSection.Settings["FCKeditor:UserFilesPath"].Value = "D:";
config.Save(ConfigurationSaveMode.Modified);