A server-side control object processes and generates a client-side user interface element for display on a web page. Multiple server-side control objects may be combined into a hierarchy of server-side control objects that cooperate to generate the resulting authoring language code, such as HTML, for display of a web page on a client. The operation of processing the client-side user interface element may include at least one of an event handling operation, a postback data handling operation, a data binding operation, and a state management operation. The state management operation relates to the state of a server-side control object.