Question

I’m working on a project that connects to Oracle. It Brings back data through a dataset. I use Linq to bind it to a collection and throw it back to be read by json. It works great but I can’t help but think – there’s got to be a better way to do this. Here’s an example of what I do. I hope it helps others. Dsp is Dataset.

List<Information> lstSearch = null;
     lstSearch = (from l in dsp.Tables[0].AsEnumerable()

                         select new Information
                         {

                             application_id = l["APPLICATION_ID"].ToString(),
                             hospital_name_1 = l["HOSPITAL_NAME_"].ToString(),
                             physical_address = l["PHYSICAL_ADDRESS"].ToString(),
                             // may have to add more here...

                         }).ToList<Information>();

// serialize and send back as a json string
System.Web.Script.Serialization.JavaScriptSerializer oSerializer =
                    new System.Web.Script.Serialization.JavaScriptSerializer();

                string sJSON = oSerializer.Serialize(lstSearch.First());

Theoretically, yes works. The “information” collection matches the html “name” tag of each control on the page which provides a nice robust binding. My concern lies with having
to go through each field name in order to populate the List<> object.

Isn’t there a specific where clause in where the collection (get/set) property matches the dataset column name thus populating the collection only if the column name (not the value) matches the data row column?

Answer 1

I’d recommend AutoMapper … see this question.

Here’s a very simple example. Make sure that your .NET type exactly mirrors the structure of your DB object or AutoMapper will not work as advertised:

namespace EnumerableDT
{
    class Program
    {
        public class Information
        {
            public int APPLICATION_ID { get; set; }
            public string HOSPITAL_NAME { get; set; }
            public string PHYSICAL_ADDRESS { get; set; }
            public string SOME_OTHER_FIELD { get; set; }
        }

        static DataSet dsp = new DataSet();

        static void Main(string[] args)
        {
            dsp.Tables.Add(BuildDataTableStructure());
            dsp.Tables[0].Rows.Add(BuildRow());

            AutoMapper.Mapper.Reset();
            AutoMapper.Mapper.CreateMap<IDataReader, Information>();

            var il = AutoMapper.Mapper.Map<IDataReader, IList<Information>>(dsp.Tables[0].CreateDataReader());

            Console.ReadLine();
        }

        static DataTable BuildDataTableStructure()
        {
            var dt = new DataTable();
            var dc = new DataColumn("APPLICATION_ID", typeof(int));
            dt.Columns.Add(dc);
            dc = new DataColumn("HOSPITAL_NAME", typeof(string));
            dt.Columns.Add(dc);
            dc = new DataColumn("PHYSICAL_ADDRESS", typeof(string));
            dt.Columns.Add(dc);
            dc = new DataColumn("SOME_OTHER_FIELD", typeof(string));
            dt.Columns.Add(dc);

            return dt;
        }

        static DataRow BuildRow()
        {
            DataRow dr = dsp.Tables[0].NewRow();
            dr["APPLICATION_ID"] = 1;
            dr["HOSPITAL_NAME"] = "The Hospital";
            dr["PHYSICAL_ADDRESS"] = "123 Main St.";
            dr["SOME_OTHER_FIELD"] = "Some Other Data";

            return dr;
        }
    }
}