/// <summary>
        /// Convert data settings to string representation
        /// </summary>
        /// <param name="settings">Settings</param>
        /// <returns>Text</returns>
        protected virtual string ComposeSettings(DataSettings settings)
        {
            if (settings == null)
                return "";

            return string.Format("DataProvider: {0}{2}DataConnectionString: {1}{2}",
                                 settings.DataProvider,
                                 settings.DataConnectionString,
                                 Environment.NewLine
                );
        }
        /// <summary>
        /// Save settings to a file
        /// </summary>
        /// <param name="settings"></param>
        public virtual void SaveSettings(DataSettings settings)
        {
            if (settings == null)
                throw new ArgumentNullException("settings");

            //use webHelper.MapPath instead of HostingEnvironment.MapPath which is not available in unit tests
            string filePath = Path.Combine(MapPath("~/App_Data/"), filename);
            if (!File.Exists(filePath))
            {
                using (File.Create(filePath))
                {
                    //we use 'using' to close the file after it's created
                }
            }

            var text = ComposeSettings(settings);
            File.WriteAllText(filePath, text);
        }
        /// <summary>
        /// Save settings to a file
        /// </summary>
        /// <param name="settings"></param>
        public virtual void SaveSettings(DataSettings settings)
        {
            if (settings == null)
            {
                throw new ArgumentNullException("settings");
            }

            //use webHelper.MapPath instead of HostingEnvironment.MapPath which is not available in unit tests
            string filePath = Path.Combine(MapPath("~/App_Data/"), filename);

            if (!File.Exists(filePath))
            {
                using (File.Create(filePath))
                {
                    //we use 'using' to close the file after it's created
                }
            }

            var text = ComposeSettings(settings);

            File.WriteAllText(filePath, text);
        }
 /// <summary>
 /// 数据提供者管理者新实例
 /// </summary>
 /// <param name="settings">Data settings</param>
 protected BaseDataProviderManager(DataSettings settings)
 {
     if (settings == null)
         throw new ArgumentNullException("settings");
     this.Settings = settings;
 }
        /// <summary>
        /// Parse settings
        /// </summary>
        /// <param name="text">Text of settings file</param>
        /// <returns>Parsed data settings</returns>
        protected virtual DataSettings ParseSettings(string text)
        {
            var shellSettings = new DataSettings();
            if (String.IsNullOrEmpty(text))
                return shellSettings;

            //Old way of file reading. This leads to unexpected behavior when a user's FTP program transfers these files as ASCII (\r\n becomes \n).
            //var settings = text.Split(new[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries);
            var settings = new List<string>();
            using (var reader = new StringReader(text))
            {
                string str;
                while ((str = reader.ReadLine()) != null)
                    settings.Add(str);
            }

            foreach (var setting in settings)
            {
                var separatorIndex = setting.IndexOf(separator);
                if (separatorIndex == -1)
                {
                    continue;
                }
                string key = setting.Substring(0, separatorIndex).Trim();
                string value = setting.Substring(separatorIndex + 1).Trim();

                switch (key)
                {
                    case "DataProvider":
                        shellSettings.DataProvider = value;
                        break;
                    case "DataConnectionString":
                        shellSettings.DataConnectionString = value;
                        break;
                    default:
                        shellSettings.RawDataSettings.Add(key, value);
                        break;
                }
            }

            return shellSettings;
        }