是否有可能(以及如何)在C#中在运行时将ConnectionString添加到app.config？

using System.Configuration;

public static void AddConnectionString(string connectionStringName, string connectionString)
{
    Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
    ConnectionStringsSection connectionStringsSection = config.GetSection("connectionStrings") as ConnectionStringsSection;

    if (connectionStringsSection != null)
    {
        ConnectionStringSettings connectionStringSettings = new ConnectionStringSettings(connectionStringName, connectionString);
        connectionStringsSection.ConnectionStrings.Add(connectionStringSettings);
        config.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection("connectionStrings");
    }
}

AddConnectionString("MyConnectionString", "Data Source=myServerAddress;Initial Catalog=myDataBase;Integrated Security=True");