读取并修改app.config

1.获取连接字符串

///
///依据连接串名字connectionName返回数据连接字符串/////////private static string GetConnectionStringsConfig(string connectionName){    string connectionString = string.Empty;    if (ConfigurationManager.ConnectionStrings[connectionName] != null)    {        connectionString = ConfigurationManager.ConnectionStrings[connectionName].ConnectionString;    }        return connectionString;}

   

2.更新连接字符串

///

        ///更新连接字符串

        ///

        ///连接字符串名称

        ///连接字符串内容

        ///数据提供程序名称

        private static void UpdateConnectionStringsConfig(string newName, string newConString, string newProviderName)
        {

            bool isModified = false;    //记录该连接串是否已经存在

            //如果要更改的连接串已经存在

            if (ConfigurationManager.ConnectionStrings[newName] != null)
            {

                isModified = true;

            }

            //新建一个连接字符串实例

            ConnectionStringSettings mySettings =

            new ConnectionStringSettings(newName, newConString, newProviderName);

            // 打开可执行的配置文件*.exe.config

            Configuration config =

            ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

            // 如果连接串已存在，首先删除它

            if (isModified)
            {

                config.ConnectionStrings.ConnectionStrings.Remove(newName);

            }

            // 将新的连接串添加到配置文件中.

            config.ConnectionStrings.ConnectionStrings.Add(mySettings);

            // 保存对配置文件所作的更改

            config.Save(ConfigurationSaveMode.Modified);

            // 强制重新载入配置文件的ConnectionStrings配置节

            ConfigurationManager.RefreshSection("ConnectionStrings");

        }

 

3.获取AppSettings指点项

 

        ///

        ///返回＊.exe.config文件中appSettings配置节的value项
        ///

        ///
        ///
        private static string GetAppConfig(string strKey)
        {
            foreach (string key in ConfigurationManager.AppSettings)
            {
                if (key == strKey)
                {
                    return ConfigurationManager.AppSettings[strKey];
                }
            }

            return null;
        }

 

4.添加更新AppSettings指点项

 

        ///

        ///在＊.exe.config文件中appSettings配置节增加一对键、值对
        ///

        ///
        ///
        private static void UpdateAppConfig(string newKey, string newValue)
        {
            bool isModified = false;

            foreach (string key in ConfigurationManager.AppSettings)
            {
                if (key == newKey)
                {
                    isModified = true;
                }
            }

            // Open App.Config of executable

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

            // You need to remove the old settings object before you can replace it

            if (isModified)
            {
                config.AppSettings.Settings.Remove(newKey);
            }

            // Add an Application Setting.

            config.AppSettings.Settings.Add(newKey, newValue);

            // Save the changes in App.config file.

            config.Save(ConfigurationSaveMode.Modified);

            // Force a reload of a changed section.

            ConfigurationManager.RefreshSection("appSettings");
        }