Dropdownlist SelectedIndexChanged Event Fetching values late

See more:

C#

ASP.NET

C#5.0

Hi guys,

I have asp.net website in c#.

i have Dropdownlist SelectedIndexChanged event, to get values.
Code

DataTable dt = new DataTable();
        SqlParameter[] p = new SqlParameter[1];
        p[0] = new SqlParameter("@RefID", Convert.ToInt32(i));
        dt = dl.GetDataWithParameters("Sp_WT_GetRef", p);//method which fill dt

        b.Text = dt.Rows[0]["unit"].ToString();
        c.Text = dt.Rows[0]["PriceInUSD"].ToString();
        a.Text = dt.Rows[0]["description"].ToString();

GetDataWithParameters Method

public DataTable GetDataWithParameters(string StoredProcedureName, SqlParameter[] param)
        {
            SqlConnection conn = null;
            try
            {
                DataTable tb = null;
                conn = conn = GetConnectionString();
                DataSet ds = SqlHelper.ExecuteDataset(conn, CommandType.StoredProcedure, StoredProcedureName, param);
                tb = ds.Tables[0];
                return tb;
            }
            catch (Exception ee)
            {
                return null;
            }
            finally
            {
                conn.Close();
            }

        }

Stored Procedure

alter Proc Sp_WT_GetRef
(@RefID int)

as

SELECT [RecID]
      ,[RefCode]
      ,[Description]
      ,[Unit]
      ,[PriceInUSD]
  FROM [tbl_WT_References]
  Where RecID = @RefID

n i have published on client server(ftp).

its taking minimum 6 seconds to gets the values...

can any one plz help me, how can i get these values fast....

Thanks