Specifies the unique DOM ID to assign to the control's input element. This is useful for situations where you need to identify the element from external Javascript code. By default, the interface manager never assigns DOM IDs to elements because it doesn't need or use them to identify UI elements.
This is different from the TControlClientID property, which is used for accessing the outer client DOM element for a control. An input control typically has both a client element and an input element.