<com:TContent ID="Content"> <com:TTextBox ID="Password" /> <com:TActiveCustomValidator ID="LoginValidate" ControlToValidate="Password" Text="Login failed." Display="Dynamic" OnServerValidate="login" ValidationGroup="UserAccountLogin" ClientSide.ObserveChanges="false"> <prop:ClientSide.OnValidationError> console.log('OnValidationError') </prop:ClientSide.OnValidationError> <prop:ClientSide.OnValidate> console.log('OnValidate'); </prop:ClientSide.OnValidate> <prop:ActiveControl.ClientSide OnLoading="console.log('loading')" OnComplete="console.log('completing')" /> </com:TActiveCustomValidator> <com:TActiveButton Text="Click" ValidationGroup="UserAccountLogin" /> </com:TContent>