The Button control provides a command button-style control that is used to post a Web Forms page back to the server.When used in a templated list such as a Repeater or DataList, many Button controls might be rendered as the list iterates over its data source. Because each of these Button controls shares the same ID, you cannot simply bind an event handler to each Button control's OnClick event to determine the particular Button that was clicked. To solve this, you use event bubbling to fire an event on the container control (in this case, the Repeater, DataList, or DataGrid), and let the container impart additional information to the event handler about the item that raised the event.
These events can be raised from a Button by specifying a CommandName property with the name of the event. When the Button is clicked, the command "bubbles" to the container control (such as Repeater), which fires its own event. The arguments for this event might contain additional information, such as a custom string or the index of the item that raised the event.
