C# : Snippets - Update Web.Config / App.Config

 
using System.Configuration;
using System.Web.Configuration; // For web.config
 

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

 
Configuration config = WebConfigurationManager.OpenWebConfiguration("~");
 

 
void SetAppSetting(String key, String value)
{
	if (config.AppSettings.Settings[key] == null)
	{
		config.AppSettings.Settings.Add(key, value);
	}
	else
	{
		config.AppSettings.Settings[key].Value = value;
	}
	config.Save(ConfigurationSaveMode.Full);
}
 

 
ConfigurationManager.RefreshSection("appSettings");