TIWCGJQGridToolbarSearch.OnBeforeClear Property
event which fires before clearing entered values (i.e.,clearToolbar is activated).It is called before clearing the data from search elements. If the event return true triggering does not occur. In this case you can construct your own search parameters and trigger the grid. Any other return value causes triggering.
published property OnBeforeClear: TIWCGJSonFunc index 03 read GetFuncValue write SetFuncValue stored IsFuncStored;