how can convert this code into linq format

Question

//Here we will add a function for register notification (will add sql dependency)
 public void RegisterNotification(DateTime currentTime)
 {
 string conStr = ConfigurationManager.ConnectionStrings["sqlConString"].ConnectionString;
 string sqlCommand = @"SELECT [ContactID],[ContactName],[ContactNo] from [dbo].[Contacts] where [AddedOn] > @AddedOn";
 //you can notice here I have added table name like this [dbo].[Contacts] with [dbo], its mendatory when you use Sql Dependency
 using (SqlConnection con = new SqlConnection(conStr))
 {
 SqlCommand cmd = new SqlCommand(sqlCommand, con);
                cmd.Parameters.AddWithValue("@AddedOn", currentTime);
 if (con.State != System.Data.ConnectionState.Open)
 {
                    con.Open();
 }
                cmd.Notification = null;
 SqlDependency sqlDep = new SqlDependency(cmd);
                sqlDep.OnChange += sqlDep_OnChange;
 //we must have to execute the command here
 using (SqlDataReader reader = cmd.ExecuteReader())
 {
 // nothing need to add here now
 }
 }