C# 配置文件appSettings段进行读写配置操作

/// <summary>  
        /// 写入值  
        /// </summary>  
        /// <param name="key"></param>  
        /// <param name="value"></param>  
        public static void SetValue(string key, string value)
        {
            //增加的内容写在appSettings段下 <add key="RegCode" value="0"/>  
            System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
            if (config.AppSettings.Settings[key] == null)
            {
                config.AppSettings.Settings.Add(key, value);
            }
            else
            {
                config.AppSettings.Settings[key].Value = value;
            }
            config.Save(ConfigurationSaveMode.Modified);
            ConfigurationManager.RefreshSection("appSettings");//重新加载新的配置文件   
        }

        /// <summary>  
        /// 读取指定key的值  
        /// </summary>  
        /// <param name="key"></param>  
        /// <returns></returns>  
        public static string GetValue(string key)
        {
            System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
            if (config.AppSettings.Settings[key] == null)
                return "";
            else
                return config.AppSettings.Settings[key].Value;
        }