public QueryExpressionData GetDataObject()
        {
            var data = new QueryExpressionData
            {
                Operation = OperationList?.SelectedItem as Operation,
                Field     = FieldList?.SelectedItem as Field,
                Value     = Value
            };

            return(data);
        }
 public void LoadFromData(QueryExpressionData data)
 {
     FieldList.SelectedItem     = data.Field;
     OperationList.SelectedItem = data.Operation;
     SetValue(data.Value);
 }