The server-side OnComboBoxTextChanged event occurs when the text in the ComboBox changes.
The event handler function receives two arguments:
The RadRibbonBar which has fired the event. This argument is of type object, but can be cast to the RadRibbonBar type.
An EventArgs object.This object has a number of properties for handling the request for the items:
Text – the new text of the ComboBox.
DropDown – the DropDown which fired the event.
Group – the group in which the DropDown is placed.