HI. I trying to populate dropdownlist with values in the database in asp.net. But its not working:(

Question

Here is my code:

    SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings[0].ConnectionString);

            SqlCommand cmd = new SqlCommand("select * from Student1", con);

            SqlDataAdapter da = new SqlDataAdapter(cmd);

            DataSet ds = new DataSet();

            da.Fill(ds);

            drpdownlist.DataTextField = ds.Tables[0].Columns["FullName"].ToString();

            drpdownlist.DataValueField = ds.Tables[0].Columns["Id"].ToString();

            drpdownlist.DataSource = ds.Tables[0];

            drpdownlist.DataBind();

Its giving problem for the first line.

Please help.