Unlike the events in the desktop app, the ASP.NET server control event is triggered and processed on the server. When the web request sends a client operation to the server, the control can raise an event on the server to respond to the client operation. This page or its sub-control processes the event, then ASP.NET will send a response back to the client. In this way, the user feels like using the desktop application. However, control developers must understand that only one client event is sent to the server, that is, the rapid event. Common user interface events (such as the mouse click or button) are not sent to the server, so it cannot be processed on the server.
