What's X

//先加入參考System.Configuration

//再using

using System.Configuration;

        //寫入設定檔

        protected void SetAppSettings(String key, String value)

        {

            Configuration oConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

            if (ConfigurationManager.AppSettings[key] != null)

                oConfig.AppSettings.Settings[key].Value = value;

            else

                oConfig.AppSettings.Settings.Add(key, value);

            oConfig.Save(ConfigurationSaveMode.Modified);

            ConfigurationManager.RefreshSection("appSettings");

        }

        //讀取設定檔

        protected String GetAppSettings(String key, String defaultValue)

        {

            if (ConfigurationManager.AppSettings[key] == null) SetAppSettings(key, defaultValue);

            return ConfigurationManager.AppSettings[key];

        }

//使用

//寫入

SetAppSettings("txtAccount",txtAccount.Text);

//讀取

txtAccount.Text = GetAppSettings("txtAccount", "");