creating a web service with paging

Question

I am creating a web service in asp.net 2.0 with c# and have a web method which looks like this:

 [WebMethod()]
    public List<Comment> GetYourSayComments(int pageNumber, int pageSize, int commentTopicId)
    {
        CommentManager cm = new CommentManager();
        return cm.GetYourSayComments(pageNumber, pageSize, commentTopicId, true);

    }

This was working greate for the services that just returned all entities, this method however returns paged results. what is the best way to return the total row count to the client?

Answer 1

You would have to create a custom type to include the count:

public class EnvelopeWithCount<T>
{
    public T Value { get; set; }
    public int RowCount { get; set; }
}

And then your web service would return the new type:

[WebMethod]
public EnvelopeWithCount<List<Comment>> GetYourSayComments(int pageNumber,
                                                           int pageSize,
                                                           int commentTopicId)
{
    CommentManager cm = new CommentManager();
    Envelope<List<Comment>> retrunVal = new Envelope<List<Comment>>();
    returnVal.Value = cm.GetYourSayComments(pageNumber,
                                            pageSize,
                                            commentTopicId,
                                            true);
    // Get the count of all rows however you need
    returnVal.RowCount = cm.GetYourSayComments(true).Count();

    return returnVal;
}