C#Winform中儲存配置資訊App.Config的類操作：

新增引用：System.Configuration;

/// <summary>
    /// 配置資訊維護
    /// </summary>
    public class AppConfig
    {
        public static Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

        /// <summary>
        /// 獲取配置值
        /// </summary>
        /// <param name="key">配置標識</param>
        /// <returns></returns>
        public static string GetValue(string key)
        {
            string result = string.Empty;
            if (config.AppSettings.Settings[key] != null)
                result = config.AppSettings.Settings[key].Value;
            return result;
        }

        /// <summary>
        /// 修改或增加配置值
        /// </summary>
        /// <param name="key">配置標識</param>
        /// <param name="value">配置值</param>
        public static void SetValue(string key, string value)
        {
            if (config.AppSettings.Settings[key] != null)
                config.AppSettings.Settings[key].Value = value;
            else
                config.AppSettings.Settings.Add(key, value);
            config.Save(ConfigurationSaveMode.Modified);
 

        }

        /// <summary>
        /// 刪除配置值
        /// </summary>
        /// <param name="key">配置標識</param>
        public static void DeleteValue(string key)
        {
            config.AppSettings.Settings.Remove(key);
        }
    }

/// <summary>
    /// 日誌操作
    /// </summary>
    public class LogAccess
    {
        /// <summary>
        /// 寫入日誌
        /// </summary>
        /// <param name="logContent"></param>
        public static void WriteLog(string logContent)
        {
            try
            {
                string logName = DateTime.Now.ToString("yyyy-MM-dd") + ".log";
                FileStream fileStream = new FileStream(logName, FileMode.Append);
                StreamWriter writer = new StreamWriter(fileStream);
                writer.WriteLine(string.Format("{0}錯誤:{1}", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss ffffff"), logContent));
                writer.Close();
                fileStream.Close();
            }
            catch 
            {
            }
        }
    }