Best practice when overriding a page life cycle event

Process Design Form Designer
1

In the Form Designer, if you add your own custom .NET code to override a page life cycle event, you must call its base._[PageEvent](sender, e).

Example

protected void Page_PreRender(object sender, EventArgs e) 
{
   base.Page_PreRender(sender, e);
   
   //Custom code
}

For more information on life cycle events, see the ASP.NET Page Life Cycle Overview MSDN article.