ASP.NET

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data;
using System.Data.SqlClient;
using System.Data.ProviderBase;
using System.Configuration;


namespace Hostel.Models.DataAccessLayer
{
    public class PersonDataSet
    {
        DataSet DS = new DataSet();
        SqlConnection Conn = new SqlConnection(ConfigurationManager.ConnectionStrings["HostelConnectionString"].ToString());       

        // Create the DataTable "Person_prs" in the Dataset and the its DataAdapter
        SqlDataAdapter PersonDataAdapter = new
        SqlDataAdapter(new SqlCommand("SELECT * FROM Person_prs", Conn));          
    }
}

<br />
Error	1	A field initializer cannot reference the non-static field, method, or property 'Hostel.Models.DataAccessLayer.PersonDataSet.Conn'<br />

using (apReportDataContext context = new apReportDataContext())
            {
                var appointments = (
                            from app in context.t_msts
                            join li in  context.Lead_In
 on app.apm_LeadID equals li.iLeadID into app_li
                            from li in app_li.DefaultIfEmpty()
                            join cs in context.custContactInfos on li.iLeadID equals cs.id into li_cs
                            from cs in li_cs.DefaultIfEmpty()
                            join apm in context.atm_appointment_type_masts on app.apm_type_id equals apm.atm_id into cs_apm
                            from apm in cs_apm.DefaultIfEmpty()


                            select new
                            {
                              app.apm_id,
                              app.apm_name,
                              app.apm_desc,
                              app.apm_start_time,
                              cs.CustomerName,
                              apm.atm_type_name,
                              
                            });

              




                grv.DataSource = appointments.Distinct();
                grv.DataBind();

            }

[Serializable]
public class Item
{
  public string ProdName { get; set; }
  public string Qty { get; set; }
}

[Serializable]
public class Order
{
  public DateTime Dt;
  public int CustomerId;
  public List<Item> Items;
}