/// <summary>
 /// Returns the default language neutral Xml file
 /// </summary>
 /// <returns></returns>
 protected virtual NSurveyDataSource GetNeutralXml(string filePath)
 {
     if (this._context.Cache[this.FileName] == null)
     {
         if (!File.Exists(filePath))
         {
             return null;
         }
         NSurveyDataSource source = new NSurveyDataSource();
         source.ReadXml(filePath);
         CacheDependency dependencies = new CacheDependency(filePath);
         this._context.Cache.Insert(this.FileName, source, dependencies);
     }
     return (NSurveyDataSource) this._context.Cache[this.FileName];
 }
 /// <summary>
 /// Returns the localized Xml file
 /// </summary>
 /// <returns></returns>
 protected virtual NSurveyDataSource GetLocalizedXml(string filePath)
 {
     if (this._context.Cache[this.FileName + CultureInfo.CurrentUICulture.TwoLetterISOLanguageName] == null)
     {
         if (!File.Exists(filePath))
         {
             return null;
         }
         NSurveyDataSource source = new NSurveyDataSource();
         source.ReadXml(filePath);
         CacheDependency dependencies = new CacheDependency(filePath);
         this._context.Cache.Insert(this.FileName + CultureInfo.CurrentUICulture.TwoLetterISOLanguageName, source, dependencies);
     }
     return (NSurveyDataSource) this._context.Cache[this.FileName + CultureInfo.CurrentUICulture.TwoLetterISOLanguageName];
 }