public virtual Expression VisitOrderBy(OrderByExpression node)
 {
     Visit(node.Source);
     if (node.FieldName is ConstantExpression)
     {
         _orderByXml.Add(string.Format("<FieldRef Name='{0}'{1} />", ((ConstantExpression)node.FieldName).Value.ToString(), node.OrderType == OrderByType.Descending ? "Ascending='FALSE'" : string.Empty));
         return(node);
     }
     throw new NotSupportedException();
 }
 public virtual Expression VisitOrderBy(OrderByExpression node)
 {
     Visit(node.Source);
     if (node.FieldName is ConstantExpression)
     {
         _orderByXml.Add(string.Format("<FieldRef Name='{0}'{1} />", ((ConstantExpression)node.FieldName).Value.ToString(), node.OrderType == OrderByType.Descending ? "Ascending='FALSE'" : string.Empty));
         return node;
     }
     throw new NotSupportedException();
 }